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1.  Mitochondrial DNA Haplogroups influence AIDS Progression 
AIDS (London, England)  2008;22(18):2429-2439.
Mitochondrial function plays a role in both AIDS progression and highly active antiretroviral therapy (HAART) toxicity, therefore we sought to determine whether mitochondrial (mt) DNA variation revealed novel AIDS Restriction Genes (ARGs), particularly as mtDNA single nucleotide polymorphisms (SNPs) are known to influence regulation of oxidative phosphorylation, reactive oxygen species (ROS) production, and apoptosis.
Retrospective cohort study.
We performed an association study of mtDNA haplogroups among 1833 European American HIV-1 patients from five US cohorts, the Multicenter AIDS Cohort Study (MACS), the San Francisco City Clinic Study (SFCC), Hemophilia Growth and Development Study (HGDS), the Multicenter Hemophilia Cohort Study (MHCS), and the AIDS Linked to Intravenous Experiences (ALIVE) cohort to determine whether the mtDNA haplogroup correlated with AIDS progression rate.
MtDNA haplogroups J and U5a were elevated among HIV-1 infected people who display accelerated progression to AIDS and death. Haplogroups Uk, H3, and IWX appeared to be highly protective against AIDS progression.
The associations found in our study appear to support a functional explanation by which mtDNA variation among haplogroups influencing ATP production, ROS generation, and apoptosis is correlated to AIDS disease progression, however repeating these results in cohorts with different ethnic backgrounds would be informative. These data suggest that mitochondrial genes are important indicators of AIDS disease progression in HIV-1 infected persons.
PMCID: PMC2699618  PMID: 19005266
Mitochondria; AIDS; HIV-1; apoptosis; disease
2.  Genetic Variants in Nuclear-Encoded Mitochondrial Genes Influence AIDS Progression 
PLoS ONE  2010;5(9):e12862.
The human mitochondrial genome includes only 13 coding genes while nuclear-encoded genes account for 99% of proteins responsible for mitochondrial morphology, redox regulation, and energetics. Mitochondrial pathogenesis occurs in HIV patients and genetically, mitochondrial DNA haplogroups with presumed functional differences have been associated with differential AIDS progression.
Methodology/Principal Findings
Here we explore whether single nucleotide polymorphisms (SNPs) within 904 of the estimated 1,500 genes that specify nuclear-encoded mitochondrial proteins (NEMPs) influence AIDS progression among HIV-1 infected patients. We examined NEMPs for association with the rate of AIDS progression using genotypes generated by an Affymetrix 6.0 genotyping array of 1,455 European American patients from five US AIDS cohorts. Successfully genotyped SNPs gave 50% or better haplotype coverage for 679 of known NEMP genes. With a Bonferroni adjustment for the number of genes and tests examined, multiple SNPs within two NEMP genes showed significant association with AIDS progression: acyl-CoA synthetase medium-chain family member 4 (ACSM4) on chromosome 12 and peroxisomal D3,D2-enoyl-CoA isomerase (PECI) on chromosome 6.
Our previous studies on mitochondrial DNA showed that European haplogroups with presumed functional differences were associated with AIDS progression and HAART mediated adverse events. The modest influences of nuclear-encoded mitochondrial genes found in the current study add support to the idea that mitochondrial function plays a role in AIDS pathogenesis.
PMCID: PMC2943476  PMID: 20877624
3.  Mitochondrial DNA Haplogroups influence lipoatrophy after Highly Active Anti-retroviral Therapy 
Although highly active retroviral therapy (HAART) has been extremely effective in lowering AIDS incidence among patients infected with HIV, certain drugs included in HAART can cause serious mitochondrial toxicities. One of the most frequent adverse events is lipoatrophy, which is the loss of subcutaneous fat in the face, arms, buttocks and/or legs as an adverse reaction to nucleoside reverse transcriptase inhibitors (NRTIs). The clinical symptoms of lipoatrophy resemble those of inherited mitochondrial diseases, which suggests that host mitochondrial genotype may play a role in susceptibility. We analyzed the association between mitochondrial haplogroup and severity of lipoatrophy in HIV-infected European American patients on HAART in the Multicenter AIDS cohort Study (MACS) and found that mitochondrial haplogroup H was strongly associated with increased atrophy (arms: p = 0.007, OR = 1.77, 95% CI = 1.17–2.69 legs: p = 0.037, OR = 1.54 95% CI = 1.03–2.31, and buttocks: p = 0.10, OR = 1.41 95% CI = 0.94–2.12). We also saw borderline significance for haplogroup T as protective against lipoatrophy (p = 0.05, OR = 0.52, 95% CI = 0.20–1.00). These data suggest that mitochondrial DNA haplogroup may influence the propensity for lipoatrophy in patients receiving NRTIs.
PMCID: PMC2742970  PMID: 19339895
lipoatrophy; mitochondrial haplogroup; NRTI; mitochondrial toxicity
4.  Kidney and liver organ transplantation in persons with human immunodeficiency virus 
Executive Summary
The objective of this analysis is to determine the effectiveness of solid organ transplantation in persons with end stage organ failure (ESOF) and human immunodeficiency virus (HIV+)
Clinical Need: Condition and Target Population
Patients with end stage organ failure who have been unresponsive to other forms of treatment eventually require solid organ transplantation. Similar to persons who are HIV negative (HIV−), persons living with HIV infection (HIV+) are at risk for ESOF from viral (e.g. hepatitis B and C) and non-viral aetiologies (e.g. coronary artery disease, diabetes, hepatocellular carcinoma). Additionally, HIV+ persons also incur risks of ESOF from HIV-associated nephropathy (HIVAN), accelerated liver damage from hepatitis C virus (HCV+), with which an estimated 30% of HIV positive (HIV+) persons are co-infected, and coronary artery disease secondary to antiretroviral therapy. Concerns that the need for post transplant immunosuppression and/or the interaction of immunosuppressive drugs with antiretroviral agents may accelerate the progression of HIV disease, as well as the risk of opportunistic infections post transplantation, have led to uncertainty regarding the overall benefit of transplantation among HIV+ patients. Moreover, the scarcity of donor organs and their use in a population where the clinical benefit of transplantation is uncertain has limited the availability of organ transplantation to persons living with ESOF and HIV.
With the development of highly active anti retroviral therapy (HAART), which has been available in Canada since 1997, there has been improved survival and health-related quality of life for persons living with HIV. HAART can suppress HIV replication, enhance immune function, and slow disease progression. HAART managed persons can now be expected to live longer than those in the pre-HAART era and as a result many will now experience ESOF well before they experience life-threatening conditions related to HIV infection. Given their improved prognosis and the burden of illness they may experience from ESOF, the benefit of solid organ transplantation for HIV+ patients needs to be reassessed.
Evidence-Based Analysis Methods
Research Questions
What are the effectiveness and cost effectiveness of solid organ transplantation in HIV+ persons with ESOF?
Literature Search
A literature search was performed on September 22, 2009 using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the Cumulative Index to Nursing & Allied Health Literature (CINAHL), the Cochrane Library, and the International Agency for Health Technology Assessment (INAHTA) for studies published from January 1, 1996 to September 22, 2009.
Inclusion Criteria
Systematic review with or without a Meta analysis, RCT, Non-RCT with controls
HIV+ population undergoing solid organ transplantation
HIV+ population managed with HAART therapy
Controls include persons undergoing solid organ transplantation who are i) HIV− ii) HCV+ mono-infected, and iii) HIV+ persons with ESOF not transplanted.
Studies that completed and reported results of a Kaplan-Meier Survival Curve analysis.
Studies with a minimum (mean or medium) follow up of 1-year.
English language citations
Exclusion Criteria
Case reports and case series were excluded form this review.
Outcomes of Interest
i) Risk of Death after transplantation
ii) Death censored graft survival (DCGS)
iii) HIV disease progression defined as the post transplant incidence of:
- opportunistic infections or neoplasms,
- CD4+ T-cell count < 200mm3, and
- any detectable level of plasma HIV viral load.
iv) Acute graft rejection,
v) Return to dialysis,
vi) Recurrence of HCV infection
Summary of Findings
No direct evidence comparing an HIV+ cohort undergoing transplantation with the same not undergoing transplantation (wait list) was found in the literature search.
The results of this review are reported for the following comparison cohorts undergoing transplantation:
i) Kidney Transplantation: HIV+ cohort compared with HIV− cohort
ii) Liver Transplantation: HIV+ cohort compared with HIV− negative cohort
iii) Liver Transplantation: HIV+ HCV+ (co-infected) cohort compared with HCV+ (mono-infected) cohort
Kidney Transplantation: HIV+ vs. HIV−
Based on a pooled HIV+ cohort sample size of 285 patients across four studies, the risk of death after kidney transplantation in an HIV+ cohort does not differ to that of an HIV− cohort [hazard ratio (HR): 0.90; 95% CI: 0.36, 2.23]. The quality of evidence supporting this outcome is very low.
Death censored graft survival was reported in one study with an HIV+ cohort sample size of 100, and was statistically significantly different (p=.03) to that in the HIV− cohort (n=36,492). However, the quality of evidence supporting this outcome was determined to be very low. There was also uncertainty in the rate of return to dialysis after kidney transplantation in both the HIV+ and HIV− groups and the effect, if any, this may have on patient survival. Because of the very low quality evidence rating, the effect of kidney transplantation on HIV-disease progression is uncertain.
The rate of acute graft rejection was determined using the data from one study. There was a nonsignificant difference between the HIV+ and HIV− cohorts (OR 0.13; 95% CI: 0.01, 2.64), although again, because of very low quality evidence there is uncertainty in this estimate of effect.
Liver Transplantation: HIV+ vs. HIV−
Based on a combined HIV+ cohort sample size of 198 patient across five studies, the risk of death after liver transplantation in an HIV+ cohort (with at least 50% of the cohort co-infected with HCV+) is statistically significantly 64% greater compared with an HIV− cohort (HR: 1.64; 95% CI: 1.32, 2.02). The quality of evidence supporting this outcome is very low.
Death censored graft survival was reported for an HIV+ cohort in one study (n=11) however the DCGS rate of the contemporaneous control HIV− cohort was not reported. Because of sparse data the quality of evidence supporting this outcome is very low indicating death censored graft survival is uncertain.
Both the CD4+ T-cell count and HIV viral load appear controlled post transplant with an incidence of opportunistic infection of 20.5%. However, the quality of this evidence for these outcomes is very low indicating uncertainty in these effects. Similarly, because of very low quality evidence there is uncertainty in the rate of acute graft rejection among both the HIV+ and HIV− groups
Liver Transplantation: HIV+/HCV+ vs. HCV+
Based on a combined HIV+/HCV+ cohort sample size of 156 from seven studies, the risk of death after liver transplantation is significantly greater (2.8 fold) in a co-infected cohort compared with an HCV+ mono-infected cohort (HR: 2.81; 95% CI: 1.47, 5.37). The quality of evidence supporting this outcome is very low. Death censored graft survival evidence was not available.
Regarding disease progression, based on a combined sample size of 71 persons in the co-infected cohort, the CD4+ T-cell count and HIV viral load appear controlled post transplant; however, again the quality of evidence supporting this outcome is very low. The rate of opportunistic infection in the co-infected cohort was 7.2%. The quality of evidence supporting this estimate is very low, indicating uncertainty in these estimates of effect.
Based on a combined HIV+/HCV+ cohort (n=57) the rate of acute graft rejection does not differ to that of an HCV+ mono-infected cohort (OR: 0.88; 95% CI: 0.44, 1.76). Also based on a combined HIV+/HCV+ cohort (n=83), the rate of HCV+ recurrence does not differ to that of an HCV+ mono-infected cohort (OR: 0.66; 95% CI: 0.27, 1.59). In both cases, the quality of the supporting evidence was very low.
Overall, because of very low quality evidence there is uncertainty in the effect of kidney or liver transplantation in HIV+ persons with end stage organ failure compared with those not infected with HIV. Examining the economics of this issue, the cost of kidney and liver transplants in an HIV+ patient population are, on average, 56K and 147K per case, based on both Canadian and American experiences.
PMCID: PMC3377507  PMID: 23074407
5.  Mitochondrial DNA variation and HIV-associated sensory neuropathy in CHARTER 
Journal of neurovirology  2012;18(6):511-520.
HIV-associated sensory neuropathy remains an important complication of combination antiretroviral therapy (CART) and HIV infection. Mitochondrial DNA haplogroups and single nucleotide polymorphisms (SNPs) have previously been associated with symptomatic neuropathy in clinical trial participants. We examined associations between mitochondrial DNA variation and HIV-associated sensory neuropathy in CHARTER. CHARTER is a U.S. based longitudinal observational study of HIV-infected adults who underwent a structured interview and standardized examination. HIV-associated sensory neuropathy was determined by trained examiners as ≥1 sign (diminished vibratory and sharp-dull discrimination or ankle reflexes) bilaterally. Mitochondrial DNA sequencing was performed and haplogroups were assigned by published algorithms. Multivariable logistic regression of associations between mitochondrial DNA SNPs, haplogroups and HIV-associated sensory neuropathy were performed. In analyses of associations of each mitochondrial DNA SNP with HIV-associated sensory neuropathy, the two most significant SNPs were at positions A12810G (odds ratio [95% confidence interval] = 0.27 [0.11-0.65]; p = 0.004) and T489C (odds ratio [95% confidence interval] = 0.41 [0.21-0.80]; p = 0.009). These synonymous changes are known to define African haplogroup L1c and European haplogroup J, respectively. Both haplogroups are associated with decreased prevalence of HIV-associated sensory neuropathy compared with all other haplogroups (odds ratio [95% confidence interval] = 0.29 [0.12-0.71]; p = 0.007 and odds ratio [95% confidence interval] = 0.42 [0.18-1.0]; p = 0.05, respectively). In conclusion, in this cohort of mostly combination antiretroviral therapy-treated subjects, two common mitochondrial DNA SNPs and their corresponding haplogroups were associated with a markedly decreased prevalence of HIV-associated sensory neuropathy.
PMCID: PMC3587171  PMID: 23073667
genetics; mitochondria; HIV-related neurological diseases; peripheral neuropathy
6.  Public-Health and Individual Approaches to Antiretroviral Therapy: Township South Africa and Switzerland Compared 
PLoS Medicine  2008;5(7):e148.
The provision of highly active antiretroviral therapy (HAART) in resource-limited settings follows a public health approach, which is characterised by a limited number of regimens and the standardisation of clinical and laboratory monitoring. In industrialized countries doctors prescribe from the full range of available antiretroviral drugs, supported by resistance testing and frequent laboratory monitoring. We compared virologic response, changes to first-line regimens, and mortality in HIV-infected patients starting HAART in South Africa and Switzerland.
Methods and Findings
We analysed data from the Swiss HIV Cohort Study and two HAART programmes in townships of Cape Town, South Africa. We included treatment-naïve patients aged 16 y or older who had started treatment with at least three drugs since 2001, and excluded intravenous drug users. Data from a total of 2,348 patients from South Africa and 1,016 patients from the Swiss HIV Cohort Study were analysed. Median baseline CD4+ T cell counts were 80 cells/μl in South Africa and 204 cells/μl in Switzerland. In South Africa, patients started with one of four first-line regimens, which was subsequently changed in 514 patients (22%). In Switzerland, 36 first-line regimens were used initially, and these were changed in 539 patients (53%). In most patients HIV-1 RNA was suppressed to 500 copies/ml or less within one year: 96% (95% confidence interval [CI] 95%–97%) in South Africa and 96% (94%–97%) in Switzerland, and 26% (22%–29%) and 27% (24%–31%), respectively, developed viral rebound within two years. Mortality was higher in South Africa than in Switzerland during the first months of HAART: adjusted hazard ratios were 5.90 (95% CI 1.81–19.2) during months 1–3 and 1.77 (0.90–3.50) during months 4–24.
Compared to the highly individualised approach in Switzerland, programmatic HAART in South Africa resulted in similar virologic outcomes, with relatively few changes to initial regimens. Further innovation and resources are required in South Africa to both achieve more timely access to HAART and improve the prognosis of patients who start HAART with advanced disease.
Comparing HIV treatment in Switzerland, where drug selection is individualized, and South Africa, where a programmatic approach is used, Matthias Egger and colleagues find similar virologic outcomes over two years.
Editors' Summary
Acquired immunodeficiency syndrome (AIDS) has killed more than 25 million people since the first reported case in 1981, and more than 30 million people are now infected with the human immunodeficiency virus (HIV), which causes AIDS. HIV destroys immune system cells (including CD4 cells, a type of lymphocyte), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected people died within 10 years of becoming infected. Then, in 1996, highly active antiretroviral therapy (HAART)—a combination of several antiretroviral drugs—was developed. Now, in resource-rich countries, clinicians provide individually tailored care for HIV-infected people by prescribing combinations of antiretroviral drugs chosen from more than 20 approved medicines. The approach to treatment of HIV in developed countries typically also includes frequent monitoring of the amount of virus in patients' blood (viral load), viral resistance testing (to see whether any viruses are resistant to specific antiretroviral drugs), and regular CD4 cell counts (an indication of immune-system health). Since the implementation of these interventions, the health and life expectancy of people with HIV has improved dramatically in these countries.
Why Was This Study Done?
The history of HIV care in resource-poor countries has been very different. Initially, these countries could not afford to provide HAART for their populations. In 2003, however, governments, international agencies, and funding bodies began to implement plans to increase HAART coverage in developing countries. By December 2006, more than a quarter of the HIV-infected people in low- and middle-income countries who urgently needed treatment were receiving HAART. However, instead of individualized treatment, HAART programs in developing countries follow a public-health approach developed by the World Health Organization. That is, drug regimens, clinical decision-making, and clinical and laboratory monitoring are all standardized. This public-health approach takes into account the realities of under-resourced health systems, but is it as effective as the individualized approach? The researchers addressed this question by comparing virologic responses (the effect of treatment on the viral load), changes to first-line (initial) therapy, and deaths in patients receiving HAART in South Africa (public-health approach) and in Switzerland (individualized approach).
What Did the Researchers Do and Find?
The researchers analyzed data collected since 2001 from more than 2,000 patients enrolled in HAART programs in two townships (Gugulethu and Khayelitsha) in Cape Town, South Africa, and from more than 1,000 patients enrolled in the Swiss HIV Cohort Study, a nationwide study of HIV-infected people. The patients in South Africa, who had a lower starting CD4 cell count and were more likely to have advanced AIDS than the patients in Switzerland, started their treatment for HIV infection with one of four first-line therapies, and about a quarter changed to a second-line therapy during the study. By contrast, 36 first-line regimens were used in Switzerland and half the patients changed to a different regimen. Despite these differences, the viral load was greatly reduced within a year in virtually all the patients and viral rebound (an increased viral load after a low measurement) developed within 2 years in a quarter of the patients in both countries. However, more patients died in South Africa than in Switzerland, particularly during the first 3 months of therapy.
What Do These Findings Mean?
These findings suggest that the public-health approach to HAART practiced in South Africa is as effective in terms of virologic outcomes as the individualized approach practiced in Switzerland. This is reassuring because it suggests that “antiretroviral anarchy” (the unregulated use of antiretroviral drugs, interruptions in drug supplies, and the lack of treatment monitoring), which is likely to lead to the emergence of viral resistance, is not happening in South Africa as some experts feared it might. Thus, these findings support the continued rollout of the public-health approach to HAART in resource-poor countries. Conversely, they also suggest that a more standardized approach to HAART could be taken in Switzerland (and in other industrialized countries) without compromising its effectiveness. Finally, the higher mortality in South Africa than in Switzerland, which partly reflects the many patients in South Africa in desperate need of HAART and their more advanced disease at the start of therapy, suggests that HIV-infected patients in South Africa and in other resource-limited countries would benefit from earlier initiation of therapy.
Additional Information.
Please access these Web sites via the online version of this summary at
The World Health Organization provides information about universal access to HIV treatment (in several languages) and on its recommendations for a public-health approach to antiretroviral therapy for HIV infection
More details on the Swiss HIV Cohort Study and on the studies in Gugulethu and Khayelitsha are available
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
HIV InSite has comprehensive information on all aspects of HIV/AIDS, including detailed information about antiretroviral therapy and links to treatment guidelines for various countries
Information is available from Avert, an international AIDS charity, on HIV and AIDS around the world and on providing AIDS drug treatment for millions
PMCID: PMC2443185  PMID: 18613745
7.  Emergence of Drug Resistance Is Associated with an Increased Risk of Death among Patients First Starting HAART 
PLoS Medicine  2006;3(9):e356.
The impact of the emergence of drug-resistance mutations on mortality is not well characterized in antiretroviral-naïve patients first starting highly active antiretroviral therapy (HAART). Patients may be able to sustain immunologic function with resistant virus, and there is limited evidence that reduced sensitivity to antiretrovirals leads to rapid disease progression or death. We undertook the present analysis to characterize the determinants of mortality in a prospective cohort study with a median of nearly 5 y of follow-up. The objective of this study was to determine the impact of the emergence of drug-resistance mutations on survival among persons initiating HAART.
Methods and Findings
Participants were antiretroviral therapy naïve at entry and initiated triple combination antiretroviral therapy between August 1, 1996, and September 30, 1999. Marginal structural modeling was used to address potential confounding between time-dependent variables in the Cox proportional hazard regression models. In this analysis resistance to any class of drug was considered as a binary time-dependent exposure to the risk of death, controlling for the effect of other time-dependent confounders. We also considered each separate class of mutation as a binary time-dependent exposure, while controlling for the presence/absence of other mutations. A total of 207 deaths were identified among 1,138 participants over the follow-up period, with an all cause mortality rate of 18.2%. Among the 679 patients with HIV-drug-resistance genotyping done before initiating HAART, HIV-drug resistance to any class was observed in 53 (7.8%) of the patients. During follow-up, HIV-drug resistance to any class was observed in 302 (26.5%) participants. Emergence of any resistance was associated with mortality (hazard ratio: 1.75 [95% confidence interval: 1.27, 2.43]). When we considered each class of resistance separately, persons who exhibited resistance to non-nucleoside reverse transcriptase inhibitors had the highest risk: mortality rates were 3.02 times higher (95% confidence interval: 1.99, 4.57) for these patients than for those who did not exhibit this type of resistance.
We demonstrated that emergence of resistance to non-nucleoside reverse transcriptase inhibitors was associated with a greater risk of subsequent death than was emergence of protease inhibitor resistance. Future research is needed to identify the particular subpopulations of men and women at greatest risk and to elucidate the impact of resistance over a longer follow-up period.
Emergence of resistance to both non-nucleoside reverse transcriptase inhibitors and protease inhibitors was associated with a higher risk of subsequent death, but the risk was greater in patients with NNRTI-resistant HIV.
Editors' Summary
In the 1980s, infection with the human immunodeficiency virus (HIV) was effectively a death sentence. HIV causes AIDS (acquired immunodeficiency syndrome) by replicating inside immune system cells and destroying them, which leaves infected individuals unable to fight off other viruses and bacteria. The first antiretroviral drugs were developed quickly, but it soon became clear that single antiretrovirals only transiently suppress HIV infection. HIV mutates (accumulates random changes to its genetic material) very rapidly and, although most of these changes (or mutations) are bad for the virus, by chance some make it drug resistant. Highly active antiretroviral therapy (HAART), which was introduced in the mid-1990s, combines three or four antiretroviral drugs that act at different stages of the viral life cycle. For example, they inhibit the reverse transcriptase that the virus uses to replicate its genetic material, or the protease that is necessary to assemble new viruses. With HAART, the replication of any virus that develops resistance to one drug is inhibited by the other drugs in the mix. As a consequence, for many individuals with access to HAART, AIDS has become a chronic rather than a fatal disease. However, being on HAART requires patients to take several pills a day at specific times. In addition, the drugs in the HAART regimens often have side effects.
Why Was This Study Done?
Drug resistance still develops even with HAART, often because patients don't stick to the complicated regimens. The detection of resistance to one drug is usually the prompt to change a patient's drug regimen to head off possible treatment failure. Although most patients treated with HAART live for many years, some still die from AIDS. We don't know much about how the emergence of drug-resistance mutations affects mortality in patients who are starting antiretroviral therapy for the first time. In this study, the researchers looked at how the emergence of drug resistance affected survival in a group of HIV/AIDS patients in British Columbia, Canada. Here, everyone with HIV/AIDS has access to free medical attention, HAART, and laboratory monitoring, and full details of all HAART recipients are entered into a central reporting system.
What Did the Researchers Do and Find?
The researchers enrolled people who started antiretroviral therapy for the first time between August 1996 and September 1999 into the HAART Observational Medical Evaluation and Research (HOMER) cohort. They then excluded anyone who was infected with already drug-resistant HIV strains (based on the presence of drug-resistance mutations in viruses isolated from the patients) at the start of therapy. The remaining 1,138 patients were followed for an average of five years. All the patients received either two nucleoside reverse transcriptase inhibitors and a protease inhibitor, or two nucleoside and one non-nucleoside reverse transcriptase inhibitor (NNRTI). Nearly a fifth of the study participants died during the follow-up period. Most of these patients actually had drug-sensitive viruses, possibly because they had neglected taking their drugs to such an extent that there had been insufficient drug exposure to select for drug-resistant viruses. In a quarter of the patients, however, HIV strains resistant to one or more antiretroviral drugs emerged during the study (again judged by looking for mutations). Detailed statistical analyses indicated that the emergence of any drug resistance nearly doubled the risk of patients dying, and that people carrying viruses resistant to NNRTIs were three times as likely to die as those without resistance to this class of antiretroviral drug.
What Do These Findings Mean?
These results provide new information about the emergence of drug-resistant HIV during HAART and possible effects on the long-term survival of patients. In particular, they suggest that clinicians should watch carefully for the emergence of resistance to NNRTIs in their patients. Because this type of resistance is often due to poor adherence to drug regimens, these results also suggest that increased efforts should be made to ensure that patients comply with the prescribed HAART regimens, especially those whose antiretroviral therapy includes NNRTIs. As with all studies in which a group of individuals who share a common characteristic are studied over time, it is possible that some other, unmeasured difference between the patients who died and those who didn't—rather than emerging drug resistance—is responsible for the observed differences in survival. Additional studies are needed to confirm the findings here, and to investigate whether specific subpopulations of patients are at particular risk of developing drug resistance and/or dying during HAART.
Additional Information.
Please access these Web sites via the online version of this summary at
US National Institute of Allergy and Infectious Diseases fact sheet on HIV infection and AIDS
US Department of Health and Human Services information on AIDS, including details of approved drugs for the treatment of HIV infection
US Centers for Disease Control and Prevention information on HIV/AIDS
Aidsmap, information on HIV and AIDS provided by the charity NAM, which includes details on antiretroviral drugs
PMCID: PMC1569883  PMID: 16984218
8.  Switching HIV Treatment in Adults Based on CD4 Count Versus Viral Load Monitoring: A Randomized, Non-Inferiority Trial in Thailand 
PLoS Medicine  2013;10(8):e1001494.
Using a randomized controlled trial, Marc Lallemant and colleagues ask if a CD4-based monitoring and treatment switching strategy provides a similar clinical outcome compared to the standard viral load-based strategy for adults with HIV in Thailand.
Please see later in the article for the Editors' Summary
Viral load (VL) is recommended for monitoring the response to highly active antiretroviral therapy (HAART) but is not routinely available in most low- and middle-income countries. The purpose of the study was to determine whether a CD4-based monitoring and switching strategy would provide a similar clinical outcome compared to the standard VL-based strategy in Thailand.
Methods and Findings
The Programs for HIV Prevention and Treatment (PHPT-3) non-inferiority randomized clinical trial compared a treatment switching strategy based on CD4-only (CD4) monitoring versus viral-load (VL). Consenting participants were antiretroviral-naïve HIV-infected adults (CD4 count 50–250/mm3) initiating non-nucleotide reverse transcriptase inhibitor (NNRTI)-based therapy. Randomization, stratified by site (21 public hospitals), was performed centrally after enrollment. Clinicians were unaware of the VL values of patients randomized to the CD4 arm. Participants switched to second-line combination with confirmed CD4 decline >30% from peak (within 200 cells from baseline) in the CD4 arm, or confirmed VL >400 copies/ml in the VL arm. Primary endpoint was clinical failure at 3 years, defined as death, new AIDS-defining event, or CD4 <50 cells/mm3. The 3-year Kaplan-Meier cumulative risks of clinical failure were compared for non-inferiority with a margin of 7.4%. In the intent to treat analysis, data were censored at the date of death or at last visit. The secondary endpoints were difference in future-drug-option (FDO) score, a measure of resistance profiles, virologic and immunologic responses, and the safety and tolerance of HAART. 716 participants were randomized, 356 to VL monitoring and 360 to CD4 monitoring. At 3 years, 319 participants (90%) in VL and 326 (91%) in CD4 were alive and on follow-up. The cumulative risk of clinical failure was 8.0% (95% CI 5.6–11.4) in VL versus 7.4% (5.1–10.7) in CD4, and the upper-limit of the one-sided 95% CI of the difference was 3.4%, meeting the pre-determined non-inferiority criterion. Probability of switch for study criteria was 5.2% (3.2–8.4) in VL versus 7.5% (5.0–11.1) in CD4 (p = 0.097). Median time from treatment initiation to switch was 11.7 months (7.7–19.4) in VL and 24.7 months (15.9–35.0) in CD4 (p = 0.001). The median duration of viremia >400 copies/ml at switch was 7.2 months (5.8–8.0) in VL versus 15.8 months (8.5–20.4) in CD4 (p = 0.002). FDO scores were not significantly different at time of switch. No adverse events related to the monitoring strategy were reported.
The 3-year rates of clinical failure and loss of treatment options did not differ between strategies although the longer-term consequences of CD4 monitoring would need to be investigated. These results provide reassurance to treatment programs currently based on CD4 monitoring as VL measurement becomes more affordable and feasible in resource-limited settings.
Trial registration NCT00162682
Please see later in the article for the Editors' Summary
Editors' Summary
About 34 million people (most of them living in low-and middle-income countries) are currently infected with HIV, the virus that causes AIDS. HIV infection leads to the destruction of immune system cells (including CD4 cells, a type of white blood cell), leaving infected individuals susceptible to other infections. Early in the AIDS epidemic, most HIV-infected individuals died within 10 years of infection. Then, in 1996, highly active antiretroviral therapy (HAART)—combined drugs regimens that suppress viral replication and allow restoration of the immune system—became available. For people living in affluent countries, HIV/AIDS became a chronic condition but, because HAART was expensive, HIV/AIDS remained a fatal illness for people living in resource-limited countries. In 2003, the international community declared HIV/AIDS a global health emergency and, in 2006, it set the target of achieving universal global access to HAART by 2010. By the end of 2011, 8 million of the estimated 14.8 million people in need of HAART in low- and middle-income countries were receiving treatment.
Why Was This Study Done?
At the time this trial was conceived, national and international recommendations were that HIV-positive individuals should start HAART when their CD4 count fell below 200 cells/mm3 and should have their CD4 count regularly monitored to optimize HAART. In 2013, the World Health Organization (WHO) recommendations were updated to promote expanded eligibility for HAART with a CD4 of 500 cells/mm3 or less for adults, adolescents, and older children although priority is given to individuals with CD4 count of 350 cells/mm3 or less. Because HIV often becomes resistant to first-line antiretroviral drugs, WHO also recommends that viral load—the amount of virus in the blood—should be monitored so that suspected treatment failures can be confirmed and patients switched to second-line drugs in a timely manner. This monitoring and switching strategy is widely used in resource-rich settings, but is still very difficult to implement for low- and middle-income countries where resources for monitoring are limited and access to costly second-line drugs is restricted. In this randomized non-inferiority trial, the researchers compare the performance of a CD4-based treatment monitoring and switching strategy with the standard viral load-based strategy among HIV-positive adults in Thailand. In a randomized trial, individuals are assigned different interventions by the play of chance and followed up to compare the effects of these interventions; a non-inferiority trial investigates whether one treatment is not worse than another.
What Did the Researchers Do and Find?
The researchers assigned about 700 HIV-positive adults who were beginning HAART for the first time to have their CD4 count (CD4 arm) or their CD4 count and viral load (VL arm) determined every 3 months. Participants were switched to a second-line therapy if their CD4 count declined by more than 30% from their peak CD4 count (CD4 arm) or if a viral load of more than 400 copies/ml was recorded (VL arm). The 3-year cumulative risk of clinical failure (defined as death, a new AIDS-defining event, or a CD4 count of less than 50 cells/mm3) was 8% in the VL arm and 7.4% in the CD4 arm. This difference in clinical failure risk met the researchers' predefined criterion for non-inferiority. The probability of a treatment switch was similar in the two arms, but the average time from treatment initiation to treatment switch and the average duration of a high viral load after treatment switch were both longer in the CD4 arm than in the VL arm. Finally, the future-drug-option score, a measure of viral drug resistance profiles, was similar in the two arms at the time of treatment switch.
What Do These Findings Mean?
These findings suggest that, in Thailand, a CD4 switching strategy is non-inferior in terms of clinical outcomes among HIV-positive adults 3 years after beginning HAART when compared to the recommended viral load-based switching strategy and that there is no difference between the strategies in terms of viral suppression and immune restoration after 3-years follow-up. Importantly, however, even though patients in the CD4 arm spent longer with a high viral load than patients in the VL arm, the emergence of HIV mutants resistant to antiretroviral drugs was similar in the two arms. Although these findings provide no information about the long-term outcomes of the two monitoring strategies and may not be generalizable to routine care settings, they nevertheless provide reassurance that using CD4 counts alone to monitor HAART in HIV treatment programs in resource-limited settings is an appropriate strategy to use as viral load measurement becomes more affordable and feasible in these settings.
Additional Information
Please access these websites via the online version of this summary at
The World Health Organization provides information on all aspects of HIV/AIDS (in several languages); its 2010 recommendations for antiretroviral therapy for HIV infection in adults and adolescents are available as well as the June 2013 Consolidated guidelines on the use of antiretroviral drugs for treating and preventing HIV infection: recommendations for a public health approach
The 2012 UNAIDS World AIDS Day Report provides up-to-date information about the AIDS epidemic and efforts to halt it
Information is available from the US National Institute of Allergy and Infectious Diseases on HIV infection and AIDS
NAM/aidsmap provides basic information about HIV/AIDS and summaries of recent research findings on HIV care and treatment
Information is available from Avert, an international AIDS charity on many aspects of HIV/AIDS, including information on the global HIV/AIDS epidemic, on HIV and AIDS in Thailand, on universal access to AIDS treatment, and on starting, monitoring and switching HIV treatment (in English and Spanish)
The UK National Health Service Choices website provides information (including personal stories) about HIV and AIDS
More information about this trial (the PHPT-3 trial) is available
Patient stories about living with HIV/AIDS are available through Avert; the nonprofit website Healthtalkonline also provides personal stories about living with HIV, including stories about HIV treatment
PMCID: PMC3735458  PMID: 23940461
9.  The Other Genome: A Systematic Review of Studies of Mitochondrial DNA Haplogroups and Outcomes of HIV Infection and Antiretroviral Therapy 
AIDS reviews  2013;15(4):213-220.
Mitochondrial toxicity is implicated in some treatment-limiting ART complications, and reports of mitochondrial dysfunction in untreated HIV infection suggest ART-independent effects of HIV. Several studies have explored associations between mtDNA haplogroups (patterns of mtDNA polymorphisms) and outcomes of HIV infection and/or ART, but findings have been inconsistent. We systematically review published studies examining mtDNA haplogroups in HIV infected persons to summarize reported outcome associations, and to highlight potential future research directions. We identified 21 articles published from 2005–2013. Multiple different phenotypes were studied; most were ART-associated metabolic outcomes (e.g. lipodystrophy, insulin resistance, and dyslipidemia). Haplogoup H was associated with the most outcomes, including AIDS progression, CD4 T cell recovery, cirrhosis (in hepatitis C co-infection), and metabolic outcomes. This review is the first to focus on the emerging area of mtDNA haplogroups in HIV, and summarizes the published literature on associations between mtDNA haplogroups and clinical outcomes in populations of European and African descent. Several reported associations require replication and ideally biological verification before definitive conclusions can be drawn, but research in this area has the potential to explain outcome disparities and impact clinical management of patients.
PMCID: PMC4001077  PMID: 24322381
HIV; Mitochondrial DNA; Haplogroups; Antiretroviral Therapy
10.  Additional Haplogroups of Toxoplasma gondii out of Africa: Population Structure and Mouse-Virulence of Strains from Gabon 
Toxoplasma gondii is found worldwide, but distribution of its genotypes as well as clinical expression of human toxoplasmosis varies across the continents. Several studies in Europe, North America and South America argued for a role of genotypes in the clinical expression of human toxoplasmosis. Genetic data concerning T. gondii isolates from Africa are scarce and not sufficient to investigate the population structure, a fundamental analysis for a better understanding of distribution, circulation, and transmission.
Methodology/Principal Findings
Seropositive animals originating from urban and rural areas in Gabon were analyzed for T. gondii isolation and genotyping. Sixty-eight isolates, including one mixed infection (69 strains), were obtained by bioassay in mice. Genotyping was performed using length polymorphism of 13 microsatellite markers located on 10 different chromosomes. Results were analyzed in terms of population structure by Bayesian statistical modeling, Neighbor-joining trees reconstruction based on genetic distances, FST and linkage disequilibrium. A moderate genetic diversity was detected. Three haplogroups and one single genotype clustered 27 genotypes. The majority of strains belonged to one haplogroup corresponding to the worldwide Type III. The remaining strains were distributed into two haplogroups (Africa 1 and 3) and one single genotype. Mouse virulence at isolation was significantly different between haplogroups. Africa 1 haplogroup was the most virulent.
Africa 1 and 3 haplogroups were proposed as being new major haplogroups of T. gondii circulating in Africa. A possible link with strains circulating in South and Central America is discussed. Analysis of population structure demonstrated a local spread within a rural area and strain circulation between the main cities of the country. This circulation, favored by human activity could lead to genetic exchanges. For the first time, key epidemiological questions were addressed for the West African T. gondii population, using the high discriminatory power of microsatellite markers, thus creating a basis for further epidemiological and clinical investigations.
Author Summary
Prevalence of human toxoplasmosis in tropical African countries usually exceeds 50%. Its role as a major opportunistic infection of AIDS patients is regularly described. Due to the lack of investigation, congenital infection is certainly underestimated in Africa. Incidence of Toxoplasma ocular disease is higher in Africa and South America than in Europe. Severe cases in immunocompetent patients were described after infection acquired in Amazonia, but nothing is known about such cases in Africa. Several studies argued for a role of genotypes in the clinical expression of human toxoplasmosis, and for a geographical structuration of Toxoplasma across continents. Genetic data concerning isolates from Africa are scarce. Here, apart from the worldwide Type III, we described two main haplogroups, Africa 1 and 3. We detected genetic exchanges between urban centers favored by trade exchange and transportation. It shows how important human influence is, even in shaping the genetic structure of a zoonotic disease agent. Finding of identical haplogroups in South America suggested that these African and American strains share a common ancestor. As a higher pathogenicity in human of South American genotypes has been described, this similarity of genotypes should encourage further clinical studies with genotype analysis in Africa.
PMCID: PMC2970538  PMID: 21072237
11.  Antiretroviral Treatment and Prevention of Peripartum and Postnatal HIV Transmission in West Africa: Evaluation of a Two-Tiered Approach 
PLoS Medicine  2007;4(8):e257.
Highly active antiretroviral treatment (HAART) has only been recently recommended for HIV-infected pregnant women requiring treatment for their own health in resource-limited settings. However, there are few documented experiences from African countries. We evaluated the short-term (4 wk) and long-term (12 mo) effectiveness of a two-tiered strategy of prevention of mother-to-child transmission of HIV (PMTCT) in Africa: women meeting the eligibility criteria of the World Health Organization (WHO) received HAART, and women with less advanced HIV disease received short-course antiretroviral (scARV) PMTCT regimens.
Methods and Findings
The MTCT-Plus Initiative is a multi-country, family-centred HIV care and treatment program for pregnant and postpartum women and their families. Pregnant women enrolled in Abidjan, Côte d'Ivoire received either HAART for their own health or short-course antiretroviral (scARV) PMTCT regimens according to their clinical and immunological status. Plasma HIV-RNA viral load (VL) was measured to diagnose peripartum infection when infants were 4 wk of age, and HIV final status was documented either by rapid antibody testing when infants were aged ≥ 12 mo or by plasma VL earlier. The Kaplan-Meier method was used to estimate the rate of HIV transmission and HIV-free survival. Between August 2003 and June 2005, 107 women began HAART at a median of 30 wk of gestation, 102 of them with zidovudine (ZDV), lamivudine (3TC), and nevirapine (NVP) and they continued treatment postpartum; 143 other women received scARV for PMTCT, 103 of them with sc(ZDV+3TC) with single-dose NVP during labour. Most (75%) of the infants were breast-fed for a median of 5 mo. Overall, the rate of peripartum HIV transmission was 2.2% (95% confidence interval [CI] 0.3%–4.2%) and the cumulative rate at 12 mo was 5.7% (95% CI 2.5%–9.0%). The overall probability of infant death or infection with HIV was 4.3% (95% CI 1.7%–7.0%) at age week 4 wk and 11.7% (95% CI 7.5%–15.9%) at 12 mo.
This two-tiered strategy appears to be safe and highly effective for short- and long-term PMTCT in resource-constrained settings. These results indicate a further benefit of access to HAART for pregnant women who need treatment for their own health.
In an observational cohort study from Côte d'Ivoire, François Dabis and colleagues report on prevention of mother-to-child HIV transmission among women receiving antiretroviral therapy according to World Health Organization recommendations.
Editors' Summary
Effective treatments are available to prevent AIDS in people who are infected with HIV, but not everyone with HIV needs to take medication. Usually, anti-HIV medication is recommended only for those whose immune systems have been significantly affected by the virus, as evidenced by symptoms or by the results of a blood test, the CD4 lymphocyte (“T cell”) count. Treating HIV usually requires a combination of three or more medications. These combinations (called HAART) must be taken every day, can cause complications, and can be expensive.
Worldwide, more than half a million children became infected with HIV each year. Most of these children acquire HIV from their mothers during pregnancy or around the time of birth. If a pregnant woman with HIV takes HAART, her chances of passing HIV to the baby are greatly reduced, but the possible side effects of HAART on the baby are not known. Also, most transmission of HIV from mothers to babies occurs in poor countries where supplies of HAART are limited. For these reasons, World Health Organization (WHO) does not recommend that every pregnant woman receive HAART to prevent HIV transmission to the baby, unless the woman needs HAART for her own health (for example if her T cells are low or she has severe symptoms of HIV infection). For pregnant women with HIV who do not need to take HAART for their own health, less complicated treatments, involving a short course of one or two HIV drugs, can be used to reduce the risk of passing HIV to the baby.
Why Was This Study Done?
The WHO recommendations for HAART in pregnancy are based on the best available evidence, but it is important to know how well they work in actual practice. The authors of this study were providing HIV treatment to pregnant women with HIV in West Africa through an established clinic program in Abidjan, Côte d'Ivoire, and wanted to see how well the WHO recommendations for HAART or short-course treatments, depending on the mother's condition, were working to protect babies from HIV infection.
What Did the Researchers Do and Find?
The researchers studied 250 HIV-infected pregnant women who received HIV medications in the Abidjan program between mid-2003 and mid-2005. In accordance with WHO guidelines, 107 women began HAART for their own health during pregnancy, and 143 women did not qualify for HAART but received other short course treatments (scARV) to prevent HIV transmission to their babies. The authors monitored mothers and babies for treatment side effects and tested the babies for HIV infection up to age 1 y.
They found that HAART was relatively safe during pregnancy, although babies born to women on HAART were more likely (26.3%) to have low birth weight than babies born to women who received scARV (12.4%). Also, 7.5% of women on HAART developed side effects requiring a change in their medications. Combining the results from HAART and scART groups, the chance of HIV transmission around the time of birth was 2.2%, increasing to 5.7% at age 1 y. (Three-quarters of the infants were breast-fed; safe water for mixing formula was not reliably available.) The study found no difference in risk of HIV infection between babies whose mothers received HAART and those whose mothers received scARV according to guidelines.
What Do These Findings Mean?
These results support the safety and effectiveness of the WHO two-tiered approach for preventing mother-to-child transmission. This study was not designed to compare HAART to scART directly, because the women who received HAART were the ones with more advanced HIV infection, which might have affected their babies in many ways.
Compared to earlier pregnancy studies of HAART in rich countries, this study of the WHO approach in West Africa showed similar success in protecting infants from HIV infection around the time of birth. Unfortunately, because formula feeding was not generally available in resource-limited settings, protection declined over the first year of life with breast-feeding, but some protection remained.
This study confirms that close monitoring of pregnant women on HAART is necessary, so that drugs can be changed if side effects develop. The study does not tell us whether using scARV in pregnancy might change the virus in ways that would make it more difficult to treat the same women with HAART later if they needed it. The reason for low birth weight in some babies born to mothers on HAART is unclear. It may be because the women who needed HAART had more severe health problems from their HIV, or it may be a result of the HAART itself.
Additional Information.
Please access these Web sites via the online version of this summary at
World Health Organization has a page on prevention of mother-to-child transmission of HIV
“Women, Children, and HIV” is a resource site from the François Xavier Bagnoud Center and UCSF
The MTCT-Plus initiative at Columbia University supports the programs in Abidjan
PMCID: PMC1949842  PMID: 17713983
12.  Delayed-type hypersensitivity (DTH) test anergy does not impact CD4 reconstitution or normalization of DTH responses during antiretroviral therapy 
Delayed-type hypersensitivity (DTH) testing is an in vivo assessment of cell-mediated immunity. Although highly active antiretroviral therapy (HAART) improves immunologic parameters, the relationship between DTH responsiveness and CD4 gains on HAART is not completely understood. We investigated CD4 reconstitution and the change in DTH responses from treatment baseline through 24 months of viral load (VL)-suppressive HAART in the U.S. Military HIV Natural History Study.
Treatment-naïve subjects with VL <400 copies/mL after ≥24 months on HAART were included (n=302). DTH testing consisted of ≥3 recall antigens, and responses were classified by the number of positive skin tests: anergic (0–1) or non-anergic (≥2). Pre-HAART DTH results were compared for the outcome of CD4 reconstitution at 24 months of HAART. Improvement in DTH responses was also analyzed for those anergic before HAART initiation.
Non-anergic responses were observed in 216 (72%) participants, while 86 (28%) individuals were anergic prior to HAART initiation. Demographically there were similar distributions of age at HIV diagnosis and HAART initiation, as well as gender and race or ethnicity. There were no significant differences between non-anergic and anergic participants in pre-HAART CD4 count (409 cells/μL, interquartile range (IQR) 315–517 vs. 373 cells/μL, IQR 228–487; p=0.104) and VL (4.3 log10 copies/mL, IQR 3.4–4.9 vs. 4.4 log10 copies/mL, IQR 3.6–5.0; p=0.292). Median CD4 gains 24 months after HAART initiation were similar between the non-anergic (220 cells/μL, IQR 115–358) and anergic groups (246 cells/μL, IQR 136–358; p=0.498). For individuals anergic before HAART initiation, DTH normalization occurred at 24 months post-HAART in the majority of participants (51 of 86, 59%). Normalization of DTH responses was not associated with CD4 count at HAART initiation (OR 0.73, 95% CI 0.47, 1.09 per 100 cells; p=0.129) nor with AIDS diagnoses prior to HAART (OR 0.34, 95% CI 0.04, 2.51; p=0.283).
DTH responsiveness has been shown to predict HIV disease progression independent of CD4 count in untreated individuals. In the setting of HAART, pre-HAART anergy does not appear to impact CD4 gains or the ability to normalize DTH responses after 24 months of VL-suppressive HAART.
PMCID: PMC3916671  PMID: 24499779
HIV; HAART; antiretroviral therapy; delayed-type hypersensitivity; DTH; CD4 cell count; anergy; anergic
13.  Y-chromosomal diversity in the population of Guinea-Bissau: a multiethnic perspective 
The geographic and ethnolinguistic differentiation of many African Y-chromosomal lineages provides an opportunity to evaluate human migration episodes and admixture processes, in a pan-continental context. The analysis of the paternal genetic structure of Equatorial West Africans carried out to date leaves their origins and relationships unclear, and raises questions about the existence of major demographic phenomena analogous to the large-scale Bantu expansions. To address this, we have analysed the variation of 31 binary and 11 microsatellite markers on the non-recombining portion of the Y chromosome in Guinea-Bissau samples of diverse ethnic affiliations, some not studied before.
The Guinea-Bissau Y chromosome pool is characterized by low haplogroup diversity (D = 0.470, sd 0.033), with the predominant haplogroup E3a*-M2 shared among the ethnic clusters and reaching a maximum of 82.2% in the Mandenka people. The Felupe-Djola and Papel groups exhibit the highest diversity of lineages and harbor the deep-rooting haplogroups A-M91, E2-M75 and E3*-PN2, typical of Sahel's more central and eastern areas. Their genetic distinction from other groups is statistically significant (P = 0.01) though not attributable to linguistic, geographic or religious criteria. Non sub-Saharan influences were associated with the presence of haplogroup R1b-P25 and particular lineages of E3b1-M78.
The predominance and high diversity of haplogroup E3a*-M2 suggests a demographic expansion in the equatorial western fringe, possibly supported by a local agricultural center. The paternal pool of the Mandenka and Balanta displays evidence of a particularly marked population growth among the Guineans, possibly reflecting the demographic effects of the agriculturalist lifestyle and their putative relationship to the people that introduced early cultivation practices into West Africa. The paternal background of the Felupe-Djola and Papel ethnic groups suggests a better conserved ancestral pool deriving from East Africa, from where they have supposedly migrated in recent times. Despite the overall homogeneity in a multiethnic sample, which contrasts with their social structure, minor clusters suggest the imprints of multiple peoples at different timescales: traces of ancestral inhabitants in haplogroups A-M91 and B-M60, today typical of hunter-gatherers; North African influence in E3b1-M78 Y chromosomes, probably due to trans-Saharan contacts; and R1b-P25 lineages reflecting European admixture via the North Atlantic slave trade.
PMCID: PMC1976131  PMID: 17662131
14.  Examination of disease based selection, demographic history and population structure in European Y chromosome haplogroup I 
Journal of human genetics  2010;55(9):613-620.
We attempted to refine the understanding of an association of Y-chromosomal haplogroup I (hg-I) with enhanced AIDS progression that had been previously reported. First, we compared the progression phenotype between hg-I and its phylogenetically closest haplogroup J (hg-J). Then, we took a candidate gene approach resequencing DDX3Y, a crucial autoimmunity gene, in hg-I and other common European Y- chromosome haplogroups looking for functional variants. We extended the genetic analyses to CD24L4 and compared and contrasted the roles of disease based selection, demographic history, and population structure shaping the contemporary genetic landscape of hg-I chromosomes. Our results confirmed and refined the AIDS progression signal to hg-I, though no gene variant was identified that can explain the disease association. Molecular evolutionary and genetic analyses of the examined loci suggested a unique evolutionary history in hg-I, probably shaped by complex interactions of selection, demographic history, and high geographical differentiation leading to the formation of distinct hg-I subhaplogroups that today are associated with HIV/AIDS onset. Clearly, further studies on Y chromosome candidate loci sequencing to discover functional variants and discern the roles of evolutionary factors are warranted.
PMCID: PMC2945452  PMID: 20574427
AIDS progression; CD24L4; DDX3Y; population growth; population structure; selection; Y chromosome
15.  Origin and Spread of Bos taurus: New Clues from Mitochondrial Genomes Belonging to Haplogroup T1 
PLoS ONE  2012;7(6):e38601.
Most genetic studies on modern cattle have established a common origin for all taurine breeds in the Near East, during the Neolithic transition about 10 thousand years (ka) ago. Yet, the possibility of independent and/or secondary domestication events is still debated and is fostered by the finding of rare mitochondrial DNA (mtDNA) haplogroups like P, Q and R. Haplogroup T1, because of its geographic distribution, has been the subject of several investigations pointing to a possible independent domestication event in Africa and suggesting a genetic contribution of African cattle to the formation of Iberian and Creole cattle. Whole mitochondrial genome sequence analysis, with its proven effectiveness in improving the resolution of phylogeographic studies, is the most appropriate tool to investigate the origin and structure of haplogroup T1.
A survey of >2200 bovine mtDNA control regions representing 28 breeds (15 European, 10 African, 3 American) identified 281 subjects belonging to haplogroup T1. Fifty-four were selected for whole mtDNA genome sequencing, and combined with ten T1 complete sequences from previous studies into the most detailed T1 phylogenetic tree available to date.
Phylogenetic analysis of the 64 T1 mitochondrial complete genomes revealed six distinct sub-haplogroups (T1a–T1f). Our data support the overall scenario of a Near Eastern origin of the T1 sub-haplogroups from as much as eight founding T1 haplotypes. However, the possibility that one sub-haplogroup (T1d) arose in North Africa, in domesticated stocks, shortly after their arrival from the Near East, can not be ruled out. Finally, the previously identified “African-derived American" (AA) haplotype turned out to be a sub-clade of T1c (T1c1a1). This haplotype was found here for the first time in Africa (Egypt), indicating that it probably originated in North Africa, reached the Iberian Peninsula and sailed to America, with the first European settlers.
PMCID: PMC3369859  PMID: 22685589
16.  mtDNA haplogroup J Modulates telomere length and Nitric Oxide production 
Oxidative stress due to the overproduction of nitric oxide (NO) and other oxygen reactive species (ROS), play a main role in the initiation and progression of the OA disease and leads to the degeneration of mitochondria. Therefore, the goal of this work is to describe the difference in telomere length of peripheral blood leukocytes (PBLs) and Nitric Oxide (NO) production between mitochondrial DNA (mtDNA) haplogroup J and non-J carriers, as indirect approaches of oxidative stress.
The telomere length of PBL was analyzed in DNA samples from 166 healthy controls (114 J and 52 non-J) and 79 OA patients (41 J and 38 non-J) by means of a validated qPCR method. The NO production was assessed in 7 carriers of the haplogroup J and 27 non-J carriers, by means of the colorimetric reaction of the Griess reagent in supernatants of cultured chondrocytes. Inducible nitric oxide synthase (iNOS) mRNA from these samples was analyzed by qPCR. Appropiated statistical analyses were performed
Carriers of the haplogroup J showed a significantly longer telomere length of PBLs than non-J carriers, regardless of age, gender and diagnosis (p = 0.025). Cultured chondrocytes carrying the mtDNA haplogroup J also showed a lower NO production than non-J carriers (p = 0.043). No significant correlations between age and telomore length of PBLs were detected neither for carriers of the haplogroup J nor for non-J carriers. A strong positive correlation between NO production and iNOS expression was also observed (correlation coefficient = 0.791, p < 0.001).
The protective effect of the mtDNA haplogroup J in the OA disease arise from a lower oxidative stress in carriers of this haplogroup, since this haplogroup is related to lower NO production and hence longer telomere length of PBLs too.
PMCID: PMC3266658  PMID: 22171676
mitochondria; osteoarthritis; cartilage; arthritis; nitric oxide; telomere
17.  Mitochondrial Genomics and CD4 T-cell Count Recovery after Antiretroviral Therapy Initiation in AIDS Clinical Trials Group Study 384 
Mitochondrial DNA (mtDNA) variation has been associated with time to progression to AIDS and adverse effects from antiretroviral therapy (ART). In this study, full mitochondrial DNA (mtDNA) sequence data from U.S.-based adult participants in the AIDS Clinical Trials Group (ACTG) study 384 was used to assess associations between mtDNA variants and CD4 T cell recovery with ART.
Full mtDNA sequence was determined using chip-based array sequencing. Sequence and CD4 cell count data was available at baseline and after ART initiation for 423 subjects with HIV RNA levels <400copies/mL plasma. The primary outcome was change in CD4 count of ≥100 cells/mm3 from baseline. Analyses were adjusted for baseline age, CD4 cell count, HIV RNA, and naïve:memory CD4 cell ratio.
Race-stratified analysis of mtDNA variants with a minor allele frequency >1% revealed multiple mtDNA variants marginally associated (P < 0.05 before Bonferroni correction) with CD4 cell recovery. The most significant SNP associations were those tagging the African L2 haplogroup, which was associated with a decreased likelihood of ≥100 cells/mm3 CD4 count increase at week 48 in non-Hispanic blacks (adjusted OR=0.17; 95% CI=0.06–0.53; P=0.002).
An African mtDNA haplogroup was associated with CD4 cell recovery after ART in this clinical trial population. These initial findings warrant replication and further investigation in order to confirm the role of mtDNA variation in CD4 cell recovery during ART.
PMCID: PMC3204178  PMID: 21792066
HIV; CD4 count; Mitochondrial DNA; Pharmacogenetics; Antiretroviral Therapy
18.  Distinguishing the co-ancestries of haplogroup G Y-chromosomes in the populations of Europe and the Caucasus 
European Journal of Human Genetics  2012;20(12):1275-1282.
Haplogroup G, together with J2 clades, has been associated with the spread of agriculture, especially in the European context. However, interpretations based on simple haplogroup frequency clines do not recognize underlying patterns of genetic diversification. Although progress has been recently made in resolving the haplogroup G phylogeny, a comprehensive survey of the geographic distribution patterns of the significant sub-clades of this haplogroup has not been conducted yet. Here we present the haplogroup frequency distribution and STR variation of 16 informative G sub-clades by evaluating 1472 haplogroup G chromosomes belonging to 98 populations ranging from Europe to Pakistan. Although no basal G-M201* chromosomes were detected in our data set, the homeland of this haplogroup has been estimated to be somewhere nearby eastern Anatolia, Armenia or western Iran, the only areas characterized by the co-presence of deep basal branches as well as the occurrence of high sub-haplogroup diversity. The P303 SNP defines the most frequent and widespread G sub-haplogroup. However, its sub-clades have more localized distribution with the U1-defined branch largely restricted to Near/Middle Eastern and the Caucasus, whereas L497 lineages essentially occur in Europe where they likely originated. In contrast, the only U1 representative in Europe is the G-M527 lineage whose distribution pattern is consistent with regions of Greek colonization. No clinal patterns were detected suggesting that the distributions are rather indicative of isolation by distance and demographic complexities.
PMCID: PMC3499744  PMID: 22588667
Y-chromosome; haplogroup G; human evolution; population genetics
19.  The Effect of Highly Active Antiretroviral Therapy on the Survival of HIV-Infected Children in a Resource-Deprived Setting: A Cohort Study 
PLoS Medicine  2011;8(6):e1001044.
This observational cohort study by Andrew Edmonds and colleagues reports that treatment with highly active antiretroviral therapy (HAART) markedly improves the survival of HIV-infected children in Kinshasa, DRC, a resource-deprived setting.
The effect of highly active antiretroviral therapy (HAART) on the survival of HIV-infected children has not been well quantified. Because most pediatric HIV occurs in low- and middle-income countries, our objective was to provide a first estimate of this effect among children living in a resource-deprived setting.
Methods and Findings
Observational data from HAART-naïve children enrolled into an HIV care and treatment program in Kinshasa, Democratic Republic of the Congo, between December 2004 and May 2010 were analyzed. We used marginal structural models to estimate the effect of HAART on survival while accounting for time-dependent confounders affected by exposure. At the start of follow-up, the median age of the 790 children was 5.9 y, 528 (66.8%) had advanced or severe immunodeficiency, and 405 (51.3%) were in HIV clinical stage 3 or 4. The children were observed for a median of 31.2 mo and contributed a total of 2,089.8 person-years. Eighty children (10.1%) died, 619 (78.4%) initiated HAART, six (0.8%) transferred to a different care provider, and 76 (9.6%) were lost to follow-up. The mortality rate was 3.2 deaths per 100 person-years (95% confidence interval [CI] 2.4–4.2) during receipt of HAART and 6.0 deaths per 100 person-years (95% CI 4.1–8.6) during receipt of primary HIV care only. The mortality hazard ratio comparing HAART with no HAART from a marginal structural model was 0.25 (95% CI 0.06–0.95).
HAART reduced the hazard of mortality in HIV-infected children in Kinshasa by 75%, an estimate that is similar in magnitude but with lower precision than the reported effect of HAART on survival among children in the United States.
Please see later in the article for the Editors' Summary
Editors' Summary
In 2009, an estimated 2.5 million children were living with HIV, the majority of whom (2.3 million) were in sub-Saharan Africa. Most (90%) of these children acquired HIV from their HIV-infected mothers during pregnancy, birth, or breastfeeding, highlighting the importance of giving effective drugs for the prevention of mother to child transmission. As such interventions are still not widely accessible or available in most resource-limited countries, where the burden of HIV is highest, every day an estimated 1,000 children were newly infected with HIV in 2009, but only 360,000 children were receiving highly active antiretroviral therapy (HAART).
Although HAART improves the survival of adults living with HIV, less is known about the degree to which HAART affects the survival of HIV-infected children—although response to antiretroviral treatment is known to differ across age groups. Furthermore, as the course of HIV disease in children is different from that in adults (partly because of the impact of the virus on the immature thymus, which can lead to high HIV RNA viremia and rapid death), it is inappropriate to extrapolate results from studies of adults to pediatric populations. Therefore, it is imperative that the effect of HAART on survival be quantified specifically in children.
Why Was This Study Done?
Most observational studies of the effects of treatment on child survival have been undertaken in high-income countries, such as Italy and the United States. As most children with HIV live in low-resource areas, where multiple factors, such as delayed presentation to care and a higher incidence of co-occurring conditions, might adversely affect treatment outcomes, there is a specific need for information on the effects of HAART in children with HIV living in low-income countries. Although some investigations have taken place in pediatric cohorts from such countries (for example, Côte d'Ivoire, Haiti, Lesotho, Thailand, and Zambia), the effect of HAART on mortality has not been accurately quantified among children in a resource-deprived setting. Therefore, in this observational clinical cohort study, the researchers investigated the effect of HAART on mortality in HIV-infected children in Kinshasa, in the Democratic Republic of the Congo (DRC).
What Did the Researchers Do and Find?
The researchers analyzed data from 790 children enrolled into an HIV program in Kinshasa, DRC, between December 2004 and May 2010 and used a statistical model (marginal structural models) to adjust for time-dependent confounding factors, such as the fact that HAART is typically initiated in sicker patients, for example, those with lower CD4 cell percentages. Assuming that all children starting HAART received it uninterruptedly throughout follow-up, using this statistical model, the researchers were able to compare the hazard ratio of death had all children initiated HAART to that had no children initiated HAART during follow-up.
In the study, 619 out of the 790 children (78.4%) initiated HAART during follow-up and were followed for a median of 31.2 months, with a median of 30 HIV care visits. Of those who started treatment, 110 (17.8%) switched to an alternative regimen because of an adverse event or treatment failure. During the 2,089.8 accrued person-years of follow-up, 80 children (10.1%) died, giving an overall mortality rate of 3.8 deaths per 100 person-years. The unadjusted mortality rate ratio comparing HAART to no HAART was 0.54. Using a marginal structural model, the researchers estimated that compared to no HAART, HAART reduced the hazard (rate) of mortality during follow-up by 75%.
What Do These Findings Mean?
These findings show that treatment with HAART markedly improved the survival of children infected with HIV in Kinshasa, DRC, and suggest that HAART is as effective in improving the survival of HIV-infected children in a severely resource-deprived country (still recovering from civil war) as in more resource-privileged settings—an important finding given that the vast majority of children receiving HAART live in resource-poor areas. This study provides additional evidence that accelerating rollout of antiretroviral therapy to children with HIV in resource-poor countries is lifesaving and effective. Future research needs to address how effective HAART is in understudied populations in resource-poor countries, such as undernourished children or those with co-infections such as tuberculosis.
Additional Information
Please access these Web sites via the online version of this summary at
The World Health Organization's Web site has more information about the treatment of children living with HIV
Médecins Sans Frontières's Campaign for Access to Essential Medicines Web site has more information on pediatric HAART
PMCID: PMC3114869  PMID: 21695087
20.  Phylogeographic history of grey wolves in Europe 
While it is generally accepted that patterns of intra-specific genetic differentiation are substantially affected by glacial history, population genetic processes occurring during Pleistocene glaciations are still poorly understood. In this study, we address the question of the genetic consequences of Pleistocene glaciations for European grey wolves. Combining our data with data from published studies, we analysed phylogenetic relationships and geographic distribution of mitochondrial DNA haplotypes for 947 contemporary European wolves. We also compared the contemporary wolf sequences with published sequences of 24 ancient European wolves.
We found that haplotypes representing two haplogroups, 1 and 2, overlap geographically, but substantially differ in frequency between populations from south-western and eastern Europe. A comparison between haplotypes from Europe and other continents showed that both haplogroups are spread throughout Eurasia, while only haplogroup 1 occurs in contemporary North American wolves. All ancient wolf samples from western Europe that dated from between 44,000 and 1,200 years B.P. belonged to haplogroup 2, suggesting the long-term predominance of this haplogroup in this region. Moreover, a comparison of current and past frequencies and distributions of the two haplogroups in Europe suggested that haplogroup 2 became outnumbered by haplogroup 1 during the last several thousand years.
Parallel haplogroup replacement, with haplogroup 2 being totally replaced by haplogroup 1, has been reported for North American grey wolves. Taking into account the similarity of diets reported for the late Pleistocene wolves from Europe and North America, the correspondence between these haplogroup frequency changes may suggest that they were associated with ecological changes occurring after the Last Glacial Maximum.
PMCID: PMC2873414  PMID: 20409299
21.  Effects of highly active antiretroviral therapy and its adherence on herpes zoster incidence: a longitudinal cohort study 
Herpes zoster (HZ) is common among HIV-infected individuals, but the impacts of highly active antiretroviral therapy (HAART) and HAART adherence on HZ risk have not been well studied.
The effects of HAART and HAART adherence on HZ incidence were evaluated by comparing HIV-infected women on HAART (HAART use group) with the HIV-infected women remaining HAART naïve (HAART naïve group) in the Women’s Interagency HIV Study (WIHS). A 1:1 matching with propensity score for predicting HAART initiation was conducted to balance background covariates at index visit, including HIV disease stage. Kaplan-Meier method was used to compare the risk of HZ development between the matched pairs. Cox proportional hazard models were used to assess the effects of HAART and HAART adherence on HZ incidence.
Through propensity score matching, 389 pairs of participants were identified and they contributed 3,909 person years after matching. The background covariates were similar between the matched pairs at the index visit. The participants had a mean age around 39 years old, and about 61% of them were Black and 22% were Latina. No significant difference in HZ risk was observed between the HAART use group and the HAART naïve group during the first year of follow-up in any analyses. In the univariate analysis, the HAART use group had marginally lower HZ risk (Hazard Ratio (HR): 0.72; 95% Confidence Interval (CI): 0.48-1.1) over the entire follow-up period. However, women with a HAART adherence level of ≥95% had significantly lower HZ risk (HR: 0.54; 95% CI: 0.31, 0.94) compared to the HAART naïve women. The association remained significant after adjusting for quality of life score and acyclovir use, but it attenuated and was no longer statistically significant after adjusting for an intermediate variable, either CD4+ T cell counts or HIV viral load.
Among adult women, we observed a significant preventive effect of long-term HAART use on HZ incidence when a HAART adherence level of ≥95% was attained, and this effect was mediated through reduction of HIV viral load and improvement of CD4+ T cell counts.
PMCID: PMC3904465  PMID: 24373482
HAART; Adherence; Herpes zoster; Incidence; Propensity score
22.  T Cell Activation Markers and African Mitochondrial DNA Haplogroups among Non-Hispanic Black Participants in AIDS Clinical Trials Group Study 384 
PLoS ONE  2012;7(8):e43803.
Mitochondrial function influences T cell dynamics and is affected by mitochondrial DNA (mtDNA) variation. We previously reported an association between African mtDNA haplogroup L2 and less robust CD4 cell recovery on antiretroviral therapy (ART) in non-Hispanic black ACTG 384 subjects. We explored whether additional T cell parameters in this cohort differed by mtDNA haplogroup.
ACTG 384 randomized ART-naïve subjects to two different nucleoside regimens with efavirenz, nelfinavir, or both. CD4 and CD8 memory and activation markers were available at baseline and week 48 on most subjects. mtDNA sequencing was performed on whole blood DNA, and haplogroups were determined. We studied non-Hispanic black subjects with HIV RNA <400 copies/mL at week 48. Analyses included Wilcoxon ranksum test and linear regression.
Data from 104 subjects were included. Major African mtDNA haplogroups included L1 (N = 25), L2 (N = 31), and L3 (N = 32). Baseline age, HIV RNA, and CD4 cells did not differ between L2 and non-L2 haplogroups. Compared to non-L2 haplogroups, L2 subjects had lower baseline activated CD4 cells (median 12% vs. 17%; p = 0.03) and tended toward lower activated CD8 cells (41% vs. 47%; p = 0.06). At 48 weeks of ART, L2 subjects had smaller decreases in activated CD4 cells (−4% vs. −11%; p = 0.01), and smaller CD4 cell increases (+95 vs. +178; p = 0.002). In models adjusting for baseline age, CD4 cells, HIV RNA, and naïve-to-memory CD4 cell ratio, haplogroup L2 was associated with lower baseline (p = 0.04) and 48-week change in (p = 0.01) activated CD4 cells.
Among ART-naïve non-Hispanic blacks, mtDNA haplogroup L2 was associated with baseline and 48-week change in T cell activation, and poorer CD4 cell recovery. These data suggest mtDNA variation may influence CD4 T cell dynamics by modulating T cell activation. Further study is needed to replicate these associations and identify mechanisms.
PMCID: PMC3433792  PMID: 22970105
23.  Y-chromosome Short Tandem Repeat Intermediate Variant Alleles DYS392.2, DYS449.2, and DYS385.2 Delineate New Phylogenetic Substructure in Human Y-chromosome Haplogroup Tree 
Croatian Medical Journal  2009;50(3):239-249.
To determine the human Y-chromosome haplogroup backgrounds of intermediate-sized variant alleles displayed by short tandem repeat (STR) loci DYS392, DYS449, and DYS385, and to evaluate the potential of each intermediate variant to elucidate new phylogenetic substructure within the human Y-chromosome haplogroup tree.
Molecular characterization of lineages was achieved using a combination of Y-chromosome haplogroup defining binary polymorphisms and up to 37 short tandem repeat loci. DNA sequencing and median-joining network analyses were used to evaluate Y-chromosome lineages displaying intermediate variant alleles.
We show that DYS392.2 occurs on a single haplogroup background, specifically I1*-M253, and likely represents a new phylogenetic subdivision in this European haplogroup. Intermediate variants DYS449.2 and DYS385.2 both occur on multiple haplogroup backgrounds, and when evaluated within specific haplogroup contexts, delineate new phylogenetic substructure, with DYS449.2 being informative within haplogroup A-P97 and DYS385.2 in haplogroups D-M145, E1b1a-M2, and R1b*-M343. Sequence analysis of variant alleles observed within the various haplogroup backgrounds showed that the nature of the intermediate variant differed, confirming the mutations arose independently.
Y-chromosome short tandem repeat intermediate variant alleles, while relatively rare, typically occur on multiple haplogroup backgrounds. This distribution indicates that such mutations arise at a rate generally intermediate to those of binary markers and Y-STR loci. As a result, intermediate-sized Y-STR variants can reveal phylogenetic substructure within the Y-chromosome phylogeny not currently detected by either binary or Y-STR markers alone, but only when such variants are evaluated within a haplogroup context.
PMCID: PMC2702739  PMID: 19480020
24.  Mitochondrial DNA Subhaplogroups L0a2 and L2a Modify Susceptibility to Peripheral Neuropathy in Malawian Adults on Stavudine Containing Highly Active Antiretroviral Therapy 
Peripheral neuropathy (PN) is one of the main toxicities associated with stavudine. Genetic variants in mitochondrial DNA (mtDNA) haplogroups have been associated with increased risk of developing PN in European non-Hispanic and black patients on stavudine containing antiretroviral therapy (ART). We investigated mtDNA haplogroups and their role in susceptibility to stavudine-induced peripheral in Malawian patients on ART.
Two hundred and fifteen adults on stavudine containing regimens were recruited from the ART clinic at Queen Elizabeth Central Hospital, Blantyre, into a cross-sectional study to investigate the effects of genetic variants in mtDNA of individuals in relation to response to treatment. Patients were categorized according to whether or not they had developed PN after a minimum of 6 months on stavudine containing ART. Whole mtDNA coding regions of each patient were sequenced, and CD4 count, viral load, and creatinine were determined. The mtDNA variation was correlated with clinical characteristics.
Fifty-three (25%) of the participants developed PN after starting stavudine containing ART. Mitochondrial DNA subhaplogroup L0a2 was independently associated with increased risk of PN in a multivariate model (odds ratio, 2.23; 95% confidence interval, 1.14 to 4.39; P = 0.019), and subhaplogroup L2a was independently associated with reduced risk of PN (odds ratio, 0.39; 95% confidence interval, 0.16 to 0.94; P = 0.036).
Genetic variation in mtDNA confers differential risk of developing PN in patients on stavudine containing ART among Malawians.
PMCID: PMC3815091  PMID: 23614993
stavudine; mtDNA; subhaplogroup; peripheral neuropathy; toxicities
25.  Mitochondrial Polymorphism A10398G and Haplogroup I Are Associated With Fuchs' Endothelial Corneal Dystrophy 
We investigated whether mitochondrial DNA (mtDNA) variants affect the susceptibility of Fuchs endothelial corneal dystrophy (FECD).
Ten mtDNA variants defining European haplogroups were genotyped in a discovery dataset consisting of 530 cases and 498 controls of European descent from the Duke FECD cohort. Association tests for mtDNA markers and haplogroups were performed using logistic regression models with adjustment of age and sex. Subset analyses included controlling for additional effects of either the TCF4 SNP rs613872 or cigarette smoking. Our replication dataset was derived from the genome-wide association study (GWAS) of the FECD Genetics Consortium, where genotypes for three of 10 mtDNA markers were available. Replication analyses were performed to compare non-Duke cases to all GWAS controls (GWAS1, N = 3200), and to non-Duke controls (GWAS2, N = 3043).
The variant A10398G was significantly associated with FECD (odds ratio [OR] = 0.72; 95% confidence interval [CI] = [0.53, 0.98]; P = 0.034), and remains significant after adjusting for smoking status (min P = 0.012). This variant was replicated in GWAS1 (P = 0.019) and GWAS2 (P = 0.036). Haplogroup I was significantly associated with FECD (OR = 0.46; 95% CI = [0.22, 0.97]; P = 0.041) and remains significant after adjusting for the effect of smoking (min P = 0.008) or rs613872 (P = 0.034).
The 10398G allele and Haplogroup I appear to confer significant protective effects for FECD. The effect of A10398G and Haplogroup I to FECD is likely independent of the known TCF4 variant. More data are needed to decipher the interaction between smoking and mtDNA haplogroups.
The nine European mitochondrial haplogroups were investigated for the susceptibility of Fuchs endothelial corneal dystrophy (FECD). A10398G and Haplogroup I were found significantly decreasing the risk of FECD.
PMCID: PMC4109404  PMID: 24917144
mitochondrial haplogroup; genetic association; oxidative stress; TCF4; smoking

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