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.
lipoatrophy; mitochondrial haplogroup; NRTI; mitochondrial toxicity
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.
Mitochondria; AIDS; HIV-1; apoptosis; disease
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.
AIDS progression; CD24L4; DDX3Y; population growth; population structure; selection; Y chromosome
Haplogroup E1b1, defined by the marker P2, is the most represented human Y chromosome haplogroup in Africa. A phylogenetic tree showing the internal structure of this haplogroup was published in 2008. A high degree of internal diversity characterizes this haplogroup, as well as the presence of a set of chromosomes undefined on the basis of a derived character. Here we make an effort to update the phylogeny of this highly diverse haplogroup by including seven mutations which have been newly discovered by direct resequencing. We also try to incorporate five previously-described markers which were not, however, reported in the 2008 tree. Additionally, during the process of mapping, we found that two previously reported SNPs required a new position on the tree. There are three key changes compared to the 2008 phylogeny. Firstly, haplogroup E-M2 (former E1b1a) and haplogroup E-M329 (former E1b1c) are now united by the mutations V38 and V100, reducing the number of E1b1 basal branches to two. The new topology of the tree has important implications concerning the origin of haplogroup E1b1. Secondly, within E1b1b1 (E-M35), two haplogroups (E-V68 and E-V257) show similar phylogenetic and geographic structure, pointing to a genetic bridge between southern European and northern African Y chromosomes. Thirdly, most of the E1b1b1* (E-M35*) paragroup chromosomes are now marked by defining mutations, thus increasing the discriminative power of the haplogroup for use in human evolution and forensics.
Successful highly active antiretroviral therapy (HAART) regimens have resulted in substantial improvements in the systemic health of HIV infected persons and increased survival times. Despite increased systemic health, the prevalence of minor HIV-associated cognitive impairment appears to be rising with increased longevity, and it remains to be seen what functional outcomes will result from these improvements. Cognitive impairment can dramatically impact functional ability and day-to-day productivity. We assessed the relationship of quality of life (QOL) and neuropsychological functioning with successful HAART treatment.
In a prospective longitudinal study, subjects were evaluated before instituting HAART (naïve) or before changing HAART regimens because current therapy failed to maintain suppression of plasma viral load (treatment failure). Subjects underwent detailed neuropsychological and neurological examinations, as well as psychological evaluation sensitive to possible confounds. Re-evaluation was performed six months after institution of the new HAART regimen and/or if plasma viral load indicated treatment failure. At each evaluation, subjects underwent ultrasensitive HIV RNA quantitative evaluation in both plasma and cerebrospinal fluid.
HAART successes performed better than failures on measures exploring speed of mental processing (p < .02). HAART failure was significantly associated with increased self-reports of physical health complaints (p < .01) and substance abuse (p < .01). An interesting trend emerged, in which HAART failures endorsed greater levels of psychological and cognitive complaints (p = .06). Analysis between neuropsychological measures and QOL scores revealed significant correlation between QOL Total and processing speed (p < .05), as well as flexibility (p < .05).
Our study investigated the relationship between HIV-associated neurocognitive impairment and quality of life. HAART failures experienced slower psychomotor processing, and had increased self-reports of physical health complaints and substance abuse. Contrariwise, HAART successes experienced improved mental processing, demonstrating the impact of successful treatment on functioning. With increasing life expectancy for those who are HIV seropositive, it is important to measure cognitive functioning in relation to the actual QOL these individuals report. The study results have implications for the optimal management of HIV-infected persons. Specific support or intervention may be beneficial for those who have failed HAART in order to decrease substance abuse and increase overall physical health.
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.
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.
To determine the effectiveness of efavirenz vs. nevirapine in initial antiretroviral therapy regimens for adults in sub-Saharan Africa
Observational cohort study
Study subjects were 2,817 HIV-infected, HAART-naïve adults who began nevirapine- or efavirenz-based HAART between January 1998 and September 2004 via a private-sector HIV/AIDS program in nine countries of southern Africa. The primary outcome was time to virologic failure (two measurements of viral loads ≥400 copies/mL). Secondary outcomes included all-cause mortality, time to viral load <400 copies/mL, pharmacy-claim adherence, and discontinuation of nevirapine or efavirenz without virologic failure.
The median follow-up period was 2.0 years (interquartile range 1.2–2.6). Patients started on nevirapine were significantly less likely than those started on efavirenz to achieve high adherence, whether defined as 100% (30.2% vs. 38.1%, p<0.002) or >90% (44.8% vs. 49.4%, p<0.02) pharmacy-claim adherence. In a multivariate analysis, patients on nevirapine had greater risk of both virologic failure (HR 1.52; 95% CI 1.24–1.86), death (2.17; 1.31–3.60), and regimen discontinuation (1.67; 1.32–2.11). Switching from nevirapine to efavirenz had no significant virologic effect, whereas switching from efavirenz to nevirapine resulted in significantly slower time to suppression (HR 0.58, 95% CI 0.35–0.93) and faster time to failure (HR 3.92; 95% CI 1.61–9.55) than remaining on efavirenz.
In initial HAART regimens, efavirenz was associated with superior virologic and clinical outcomes than nevirapine, suggesting that efavirenz might be the preferred non-nucleoside reverse transcriptase inhibitor in resource-limited settings. However, its higher cost and potential teratogenicity are important barriers to implementation.
Effectiveness; HAART; Efavirenz; Nevirapine; Southern Africa
Chronic hepatitis B (CH-B) is common among HIV-infected individuals and increases liver-related mortality in the absence of highly active antiretroviral therapy (HAART). The impact of CH-B on long-term HAART outcomes has not been fully characterized.
To address this question, HAART initiators enrolled in the Multicenter AIDS Cohort Study (MACS) were retrospectively analyzed. Subjects were classified by hepatitis B category based on serology at the time of HAART initiation. The association of CH-B with mortality, AIDS defining illnesses, CD4 rise, and HIV suppression was assessed using regression analysis.
Of 816 men followed for a median of 7 years on HAART, 350 were never HBV infected, 357 had past infection, 45 had CH-B, and 64 were only core-antibody positive. Despite HAART, AIDS-related mortality was the most common cause of death (8.3/1000 person-years (PYs)). It was highest in those with CH-B (17/1000 PYs, 95% CI 7.3, 42) and lowest among never HBV infected (2.9/1000 PYs, 95% CI 1.4, 6.4). In a multivariable model, patients with CH-B had a 2.7-fold higher incidence of AIDS-related mortality compared to those never infected (P=0.08). Non-AIDS-related mortality was also highest among those with CH-B (22/1000 PYs), primarily due to liver disease (compared to never infected, adjusted HR 4.1, p=0.04). There was no significant difference in AIDS defining events, HIV RNA suppression, and CD4 increase.
In HIV-infected patients receiving long-term HAART, HBV status did not influence HIV suppression or CD4 increase. However, mortality was highest among those with CH-B and was mostly due to liver disease despite HBV-active HAART.
hepatitis B; HIV; HAART; CD4; mortality; isolated core hepatitis B
The ability of the Y chromosome to retain a record of its evolution has seen it become an essential tool of molecular anthropology. In the last few years, however, it has also found use in forensic genetics, providing information on the geographic origin of individuals. This has been aided by the development of efficient screening methods and an increased knowledge of geographic distribution. In this study, we describe the development of single base extension assays used to resolve 61 Y chromosome haplogroups, mainly within haplogroups A, B and E, found in Africa.
Seven multiplex assays, which incorporated 60 Y chromosome markers, were developed. These resolved Y chromosomes to 61 terminal branches of the major African haplogroups A, B and E, while also including a few Eurasian haplogroups found occasionally in African males. Following its validation, the assays were used to screen 683 individuals from Southern Africa, including south eastern Bantu speakers (BAN), Khoe-San (KS) and South African Whites (SAW). Of the 61 haplogroups that the assays collectively resolved, 26 were found in the 683 samples. While haplogroup sharing was common between the BAN and KS, the frequencies of these haplogroups varied appreciably. Both groups showed low levels of assimilation of Eurasian haplogroups and only two individuals in the SAW clearly had Y chromosomes of African ancestry.
The use of these single base extension assays in screening increased haplogroup resolution and sampling throughput, while saving time and DNA. Their use, together with the screening of short tandem repeat markers would considerably improve resolution, thus refining the geographic ancestry of individuals.
Sustained combination of HIV prevention strategies is essential to curb the spread of the HIV/AIDS epidemic. The use of highly active antiretroviral therapy (HAART) decreases morbidity and mortality, as well as HIV transmission, among treated individuals. The concept of ‘treatment as prevention’ is dependent on HAART’s ability to sustain HIV-1 RNA virological suppression at the individual and population levels, and has been demonstrated in studies evaluating transmission in mother-to-child, sero-discordant couples and large treated populations. The worldwide expansion of maximally effective antiretroviral drug regimens has been coupled with concerns regarding the magnitude of the financial investment required. However, HAART’s compounding effect on reduced morbidity, mortality and transmission makes the expansion of HAART coverage highly cost-averting. Building on a mathematical model that evaluated the impact of expanded HAART access on viral load in a Canadian setting, we demonstrate that an investment of CA$249 million over the lifetime of treated individuals would result in a net gain of CA$2.1 billion over 30 years. This provides a powerful economic incentive to rapidly scale up HAART access worldwide.
Highly active antiretroviral therapy (HAART); HIV; incidence; mortality; cost-aversion
Although a dramatic decrease in AIDS progression has been observed after Highly Active Anti Retroviral Therapy (HAART) in both low- and high-resource settings, few data support that fact in low-resource settings.
This study describes the incidence of AIDS-defining illnesses (ADI) after HAART initiation and analyzes their risk factors in a low-resource setting. A focus was put on CD4 cell counts and viral load measurements.
404 HIV-1-infected Senegalese adult patients were enrolled in a prospective observational cohort and data censored as of April 2008. A Poisson regression was used to model the incidence of ADIs over two periods and to assess its association with baseline variables, current CD4, current viral load, CD4 response, and virological response.
ADI incidence declined from 20.5 ADIs per 100 person-years, 95% CI = [16.3;25.8] during the first year to 4.3, 95% CI = [2.3;8.1] during the fourth year but increased afterwards. Before 42 months, the decrease was greater in patients with clinical stage CDC-C at baseline and with a viral load remaining below 1000 cp/mL but was uniform across CD4 strata (p = 0.1). After 42 months, 293 patients were still at risk. The current CD4 and viral load were associated with ADI incidence (decrease of 21% per 50 CD4/mm3 and of 61% for patients with a viral load < 1000 cp/mL).
During the first four years, a uniform decline of ADI incidence was observed even in patients with low CD4-cell counts at HAART initiation as long as the viral load remained undetectable. An increase was noted later in patients with immunologic and virological failures but also in patients with only virological failure.
To examine response to highly active antiretroviral therapy (HAART) among a sample of treatment-experienced patients in the late stage of human immunodeficiency virus (HIV) infection in residential health care facilities (RHCFs) in New York City facilities designated for HIV/AIDS (acquired immunodeficiency syndrome) when access and adherence are maximized.
Medical record review of 111 patients.
Demographics were mean age 42 years; 58% male; 60% African-American; 31% Hispanic; 57% injection drug users (IDUs); 23% with history of dementia; 52% hepatitis C virus (HCV) antibody seropositive; 80% on HAART, of whom 18% had lipodystrophy. Of 88 patients on HAART, 52% had a decreased viral load (>1/2log) versus 13% of 23 not on HAART (P<.05); a>1/2log viral load increase was seen in 8% and 35%, respectively (P<.05). Those with viral load increase were more likely than those with stable/decreased viral load to be IDUs (71% vs. 64%) and to have HCV seropositivity (86% vs. 53%), even with similar initial CD4+ cell count, viral load, and follow-up time.
In a predominantly minority IDU population who are treatment experienced, 50% of the patients successfully responded to treatment with supervised therapy. The RHCFs in New York City provide a unique opportunity to examine further factors associated with response to HAART in an environment in which medication administration and adherence are maximized and monitored carefully.
Advanced HIV; HAART; Hepatitis C Seropositivity; IDUs; Residential Health Care Facilities; Substance Abuse; Viral Load
Epidemiological case-control studies have revealed associations between mitochondrial haplogroups and the onset and/or progression of various multifactorial diseases. For instance, mitochondrial haplogroup T was previously shown to be associated with vascular diseases, including coronary artery disease and diabetic retinopathy. In contrast, haplogroup H, the most frequent haplogroup in Europe, is often found to be more prevalent in healthy control subjects than in patient study groups. However, justifications for the assumption that haplogroups are functionally distinct are rare. Therefore, we attempted to compare differences in mitochondrial function between haplogroup H and T cybrids.
Mitochondrial haplogroup H and T cybrids were generated by fusion of HEK293 cells devoid of mitochondrial DNA with isolated thrombocytes of individuals with the respective haplogroups. These cybrid cells were analyzed for oxidative phosphorylation (OXPHOS) enzyme activities, mitochondrial DNA (mtDNA) copy number, growth rate and susceptibility to reactive oxygen species (ROS). We observed that haplogroup T cybrids have higher survival rate when challenged with hydrogen peroxide, indicating a higher capability to cope with oxidative stress.
The results of this study show that functional differences exist between HEK293 cybrid cells which differ in mitochondrial genomic background.
Aims: To assess the "real life" effectiveness of different antiretroviral therapies (ART).
Methods: A retrospective multicentre observational study in 150 HIV-1 vertically infected children on the progression to AIDS (study A), and in 61 HIV-1 infected children on the evolution of the most relevant markers of progression (study B). All children were categorised into four groups: untreated (NT); on monotherapy (MT); on combination therapy (dual-ART); and on potent ART (HAART).
Results: No child in the HAART group progressed to AIDS, whereas 14 children in the NT and seven in the MT groups progressed to AIDS, respectively, the differences being statistically significant. There was a mean increase of 8 units of %CD4+ per year; this was greater in the HAART group than in the other groups. The mean decrease in viral load was 0.65 log10 copies/ml per year; this was greater in the HAART group than in the NT and MT groups. The HAART group had the lowest probability of returning to baseline %CD4+ and viral load.
Conclusion: Potent ART had the greatest protective effect against progression to AIDS in this observational study.
To evaluate the effects of previously reported host genetics factors that influence cytomegalovirus (CMV) retinitis incidence, progression to AIDS, and efficacy of highly active antiretroviral therapy (HAART) for mortality, retinitis progression, and retinal detachment in patients with CMV retinitis and AIDS in the era of HAART.
Prospective, multicenter, observational study.
Cox proportional hazards model based genetic association tests examined the influence of IL-10R1_S420L, CCR5Δ32, CCR2-V64I, CCR5 P1, and SDF-3`A polymorphisms among patients with mortality, retinitis progression, and retinal detachment. Participants were 203 European American and 117 African American patients with AIDS and CMV retinitis.
European American patients with the CCR5 +.P1.+ promoter haplotype showed increased risk for mortality (HR=1.83; 95% CI: 1.00–3.40; P=0.05). Although the same haplotype also trended for increased risk for mortality in African American patients, the result was not significant (HR=2.28; 95% CI: 0.93–5.60; P=0.07). However, this haplotype was associated with faster retinitis progression in African Americans (HR=5.22; 95% CI: 1.54–17.71; P=0.007). Increased risk of retinitis progression was also evident for African American patients with the SDF1-3′A variant (HR=3.89; 95% CI: 1.42–10.60; P=0.008). In addition, the SDF1-3′A variant increased the retinal detachment risk in this patient group (HR=3.05; 95% CI: 1.01–9.16; P=0.05).
Besides overall immune health, host genetic factors influence mortality, retinitis progression, and retinal detachment in patients with AIDS and CMV retinitis that are receiving HAART.
Long-term remission of HIV-1 disease can be readily achieved by combinations of highly effective antiretroviral therapy (HAART). However, a residual persistent immune activation caused by circulating non infectious particles or viral proteins is observed under HAART and might contribute to an higher risk of non-AIDS pathologies and death in HIV infected persons. A sustained immune activation supports lipid dysmetabolism and increased risk for development of accelerated atehrosclerosis and ischemic complication in virologically suppressed HIV-infected persons receiving HAART.
While several HIV proteins have been identified and characterized for their ability to maintain immune activation, the role of HIV-p17, a matrix protein involved in the viral replication, is still undefined.
Here, we report that exposure of macrophages to recombinant human p17 induces the expression of proinflammatory and proatherogenic genes (MCP-1, ICAM-1, CD40, CD86 and CD36) while downregulating the expression of nuclear receptors (FXR and PPARγ) that counter-regulate the proinflammatory response and modulate lipid metabolism in these cells. Exposure of macrophage cell lines to p17 activates a signaling pathway mediated by Rack-1/Jak-1/STAT-1 and causes a promoter-dependent regulation of STAT-1 target genes. These effects are abrogated by sera obtained from HIV-infected persons vaccinated with a p17 peptide. Ligands for FXR and PPARγ counteract the effects of p17.
The results of this study show that HIV p17 highjacks a Rack-1/Jak-1/STAT-1 pathway in macrophages, and that the activation of this pathway leads to a simultaneous dysregulation of immune and metabolic functions. The binding of STAT-1 to specific responsive elements in the promoter of PPARγ and FXR and MCP-1 shifts macrophages toward a pro-atherogenetic phenotype characterized by high levels of expression of the scavenger receptor CD36. The present work identifies p17 as a novel target in HIV therapy and grounds the development of anti-p17 small molecules or vaccines.
Little is known about pregnancy patterns and levels of HIV RNA in HIV-infected women conceiving on highly-active antiretroviral therapy (HAART) with non-suppressed viral load (VL), nor their therapeutic management.
Linear mixed models were fitted to study changes in VL and potential associated factors including HAART type/duration and immune status among 127 women receiving HAART at conception with detectable VL enrolled in the prospective European Collaborative Study.
Median duration of HAART at conception was 10 months. Seventy-eight (61%) women conceived on PI-based HAART. Seventy-two (57%) women remained on the same HAART regimen throughout pregnancy, 24 (19%) switched regimens and 31 (24%) interrupted HAART during early pregnancy. The intention-to-treat model indicated constant VL up to 10 gestational weeks; thereafter levels decreased significantly, by 0.06 log10 copies/ml weekly until delivery. At baseline, immune status was significantly associated with HIV RNA levels. Excluding treatment-interrupters, there was no significant difference in VL slope between women who did and did not modify their HAART regimens (p=0.14); women conceiving on NNRTI-based HAART had consistently lower VL throughout pregnancy than those on PI-based HAART (p=0.02). Most (64/103, 62%) women had detectable VL within four weeks of delivery (median 2.40 log10 copies/ml). The MTCT rate overall was 1.72% (95%CI 0.21-6.1%).
Practices regarding management of women conceiving on HAART with detectable VL vary in Western Europe. The existence of this group of pregnant women highlights the need for improved monitoring of and support for treated women before they become pregnant, as well as during pregnancy itself.
HIV; pregnancy; HIV RNA; HAART
Population history can be reflected in group genetic ancestry, where genomic variation captured by the mitochondrial DNA (mtDNA) and non-recombining portion of the Y chromosome (NRY) can separate female- and male-specific admixture processes. Genetic ancestry may influence genetic association studies due to differences in individual admixture within recently admixed populations like African Americans.
We evaluated the genetic ancestry of Senegalese as well as European Americans and African Americans from Philadelphia. Senegalese mtDNA consisted of ∼12% U haplotypes (U6 and U5b1b haplotypes, common in North Africa) while the NRY haplotypes belonged solely to haplogroup E. In Philadelphia, we observed varying degrees of admixture. While African Americans have 9–10% mtDNAs and ∼31% NRYs of European origin, these results are not mirrored in the mtDNA/NRY pools of European Americans: they have less than 7% mtDNAs and less than 2% NRYs from non-European sources. Additionally, there is <2% Native American contribution to Philadelphian African American ancestry and the admixture from combined mtDNA/NRY estimates is consistent with the admixture derived from autosomal genetic data. To further dissect these estimates, we have analyzed our samples in the context of different demographic groups in the Americas.
We found that sex-biased admixture in African-derived populations is present throughout the Americas, with continual influence of European males, while Native American females contribute mainly to populations of the Caribbean and South America. The high non-European female contribution to the pool of European-derived populations is consistently characteristic of Iberian colonization. These data suggest that genomic data correlate well with historical records of colonization in the Americas.
The risk of squamous intra-epithelial lesions (SIL) is higher in HIV-positive women. As these women begin to live longer due to highly active antiretroviral therapy (HAART), their risk of cervical cancer may increase. Few data exist regarding the effect of HAART on the incidence and progression of SIL in HIV-positive African women. The aim of this study was to evaluate the effect of HAART on the incidence and progression of SIL in HIV-positive women in South Africa.
A prospective observational study of HIV-seropositive women was conducted over 5 years in an HIV treatment clinic in Johannesburg, South Africa. The participants consisted of 601 women on and off HAART who had repeat Pap smears greater than 6 months apart. The effect of HAART use on incidence and progression rates of SIL was determined using multivariate Poisson regression to obtain incidence rate ratios (IRRs), adjusted for age, CD4 count and other potential confounders.
Median follow-up time was 445 days (inter-quartile range 383, 671). The crude rate of incidence of any SIL was 15.9 episodes (95% confidence limit (CL) 12.7, 19.9) per 100 person-years; the crude rate of all progression of cervical dysplasia among women was 13.5 episodes (95% CL 11.3, 16.1) per 100 person-years. HAART use was associated with a robust reduction in the rate of incidence and progression of cervical lesions, adjusted IRR=0.55 (95% CL 0.37, 0.80). Sensitivity analyses confirmed this main association held for incidence and progression when they were considered separately, and that the result was not dependent on the length of HAART exposure.
HAART use was associated with a reduction in the rate of both incidence and progression of cervical lesions among HIV-positive women.
HAART effect; cervical dysplasia; HIV-positive women; South Africa
Objectives To explore the association between a stable partnership and clinical outcome in HIV infected patients receiving highly active antiretroviral therapy (HAART).
Design Prospective cohort study of adults with HIV (Swiss HIV cohort study).
Setting Seven outpatient clinics throughout Switzerland.
Participants The 3736 patients in the cohort who started HAART before 2002 (median age 36 years, 29% female, median follow up 3.6 years).
Main outcome measures Time to AIDS or death (primary endpoint), death alone, increases in CD4 cell count of at least 50 and 100 above baseline, optimal viral suppression (a viral load below 400 copies/ml), and viral rebound.
Results During follow up 2985 (80%) participants reported a stable partnership on at least one occasion. When starting HAART, 52% (545/1042) of participants reported a stable partnership; after five years of follow up 46% (190/412) of participants reported a stable partnership. In an analysis stratified by previous antiretroviral therapy and clinical stage when starting HAART (US Centers for Disease Control and Prevention group A, B, or C), the adjusted hazard ratio for progression to AIDS or death was 0.79 (95% confidence interval 0.63 to 0.98) for participants with a stable partnership compared with those without. Adjusted hazards ratios for other endpoints were 0.59 (0.44 to 0.79) for progression to death, 1.15 (1.06 to 1.24) for an increase in CD4 cells of 100 counts/μl or more, and 1.06 (0.98 to 1.14) for optimal viral suppression.
Conclusions A stable partnership is associated with a slower rate of progression to AIDS or death in HIV infected patients receiving HAART.
Two hundred and three individuals classified as white were tested for 11 single nucleotide polymorphisms plus two insertion/deletions in their Y-chromosomes. A subset of these individuals (n = 172) was also screened for sequences in the first hypervariable segment of their mitochondrial DNA (mtDNA). In addition, complementary studies were done for 11 of the 13 markers indicated above in 54 of 107 black subjects previously investigated in this southern Brazilian population. The prevalence of Y-chromosome haplogroups among whites was similar to that found in the Azores (Portugal) or Spain, but not to that of other European countries. About half of the European or African mtDNA haplogroups of these individuals were related to their places of origin, but not their Amerindian counterparts. Persons classified in these two categories of skin color and related morphological traits showed distinct genomic ancestries through the country. These findings emphasize the need to consider in Brazil, despite some general trends, a notable heterogeneity in the pattern of admixture dynamics within and between populations/groups.
admixture dynamics; mtDNA; Y-chromosome markers
This study aims to establish the likely origin of EEJ (Eastern European Jews) by genetic distance analysis of autosomal markers and haplogroups on the X and Y chromosomes and mtDNA.
According to the autosomal polymorphisms the investigated Jewish populations do not share a common origin, and EEJ are closer to Italians in particular and to Europeans in general than to the other Jewish populations. The similarity of EEJ to Italians and Europeans is also supported by the X chromosomal haplogroups. In contrast according to the Y-chromosomal haplogroups EEJ are closest to the non-Jewish populations of the Eastern Mediterranean. MtDNA shows a mixed pattern, but overall EEJ are more distant from most populations and hold a marginal rather than a central position. The autosomal genetic distance matrix has a very high correlation (0.789) with geography, whereas the X-chromosomal, Y-chromosomal and mtDNA matrices have a lower correlation (0.540, 0.395 and 0.641 respectively).
The close genetic resemblance to Italians accords with the historical presumption that Ashkenazi Jews started their migrations across Europe in Italy and with historical evidence that conversion to Judaism was common in ancient Rome. The reasons for the discrepancy between the biparental markers and the uniparental markers are discussed.
This article was reviewed by Damian Labuda (nominated by Jerzy Jurka), Kateryna Makova and Qasim Ayub (nominated by Dan Graur).
The progression of HIV disease has been markedly slowed by the use of highly active antiretroviral therapy (HAART). However, substantial genetic variation was observed to occur among different people in the decay rate of viral loads caused by HAART. The characterization of specific genes involved in HIV dynamics is central to design personalized drugs for the prevention of this disease, but usually cannot be addressed by experimental methods alone rather than require the help of mathematical and statistical methods. A novel statistical model has been recently developed to detect genetic variants that are responsible for the shape of HAART-induced viral decay curves. This model was employed to an HIV/AIDS trial, which led to the identification of a major genetic determinant that triggers an effect on HIV dynamics. This detected major genetic determinant also affects several clinically important parameters, such as half-lives of infected cells and HIV eradication times.
Hardy-weinberg equilibrium; bi-exponential function; quantitative trait loci; HIV dynamics; functional mapping.
Human Y-chromosome haplogroup structure is largely circumscribed by continental boundaries. One notable exception to this general pattern is the young haplogroup R1a that exhibits post-Glacial coalescent times and relates the paternal ancestry of more than 10% of men in a wide geographic area extending from South Asia to Central East Europe and South Siberia. Its origin and dispersal patterns are poorly understood as no marker has yet been described that would distinguish European R1a chromosomes from Asian. Here we present frequency and haplotype diversity estimates for more than 2000 R1a chromosomes assessed for several newly discovered SNP markers that introduce the onset of informative R1a subdivisions by geography. Marker M434 has a low frequency and a late origin in West Asia bearing witness to recent gene flow over the Arabian Sea. Conversely, marker M458 has a significant frequency in Europe, exceeding 30% in its core area in Eastern Europe and comprising up to 70% of all M17 chromosomes present there. The diversity and frequency profiles of M458 suggest its origin during the early Holocene and a subsequent expansion likely related to a number of prehistoric cultural developments in the region. Its primary frequency and diversity distribution correlates well with some of the major Central and East European river basins where settled farming was established before its spread further eastward. Importantly, the virtual absence of M458 chromosomes outside Europe speaks against substantial patrilineal gene flow from East Europe to Asia, including to India, at least since the mid-Holocene.
Y chromosome; haplogroup R1a; human evolution; population genetics
To describe the long term outcome of patients who interrupted highly active antiretroviral therapy (HAART) once, identify the variables associated with earlier need to re-start HAART, and the response when therapy was resumed. A retrospective observational cohort of 66 adult patients with HIV-1 infection who interrupted HAART with a CD4+cell count ≥350 cells/μL and undetectable viral load (VL) was performed. The pre-established CD4+ cell count for restarting therapy was 300cells/μL. Cox regression was used to analyse the variables associated with earlier HAART reinitiation.
The median follow-up was 209 weeks (range, 64–395). Rates of HIV-related or possible HIV-related events were 0.37 (one case of acute retroviral syndrome) and 1.49 per 100 patient-years, respectively. Two patients died after re-starting therapy and having reached undetectable VL. Three patients suffered a sexually transmitted disease while off therapy. Fifty patients (76%) resumed therapy after a median of 97 weeks (range, 17–267). Age, a nadir of CD4+ <250 cells/μL, and a mean VL during interruption of >10,000 copies/ml were independent predictors for earlier re-start. The intention-to-treat success rate of the first HAART resumed regimen was 85.4%. There were no differences by regimen used, nor between regimens that were the same as or different from the one that had been interrupted.
Our data suggest highly active antiretroviral therapy may be interrupted in selected patients because in these patients, when the HAART is restarted, the viral and clinical response may be achieved.
HIV-1; Antiretroviral therapy; Treatment interruption; Outcome; Cohort study