PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-5 (5)
 

Clipboard (0)
None

Select a Filter Below

Journals
Year of Publication
Document Types
1.  Association of Genetic Variants in Complement Factor H and Factor H-Related Genes with Systemic Lupus Erythematosus Susceptibility 
PLoS Genetics  2011;7(5):e1002079.
Systemic lupus erythematosus (SLE), a complex polygenic autoimmune disease, is associated with increased complement activation. Variants of genes encoding complement regulator factor H (CFH) and five CFH-related proteins (CFHR1-CFHR5) within the chromosome 1q32 locus linked to SLE, have been associated with multiple human diseases and may contribute to dysregulated complement activation predisposing to SLE. We assessed 60 SNPs covering the CFH-CFHRs region for association with SLE in 15,864 case-control subjects derived from four ethnic groups. Significant allelic associations with SLE were detected in European Americans (EA) and African Americans (AA), which could be attributed to an intronic CFH SNP (rs6677604, in intron 11, Pmeta = 6.6×10−8, OR = 1.18) and an intergenic SNP between CFHR1 and CFHR4 (rs16840639, Pmeta = 2.9×10−7, OR = 1.17) rather than to previously identified disease-associated CFH exonic SNPs, including I62V, Y402H, A474A, and D936E. In addition, allelic association of rs6677604 with SLE was subsequently confirmed in Asians (AS). Haplotype analysis revealed that the underlying causal variant, tagged by rs6677604 and rs16840639, was localized to a ∼146 kb block extending from intron 9 of CFH to downstream of CFHR1. Within this block, the deletion of CFHR3 and CFHR1 (CFHR3-1Δ), a likely causal variant measured using multiplex ligation-dependent probe amplification, was tagged by rs6677604 in EA and AS and rs16840639 in AA, respectively. Deduced from genotypic associations of tag SNPs in EA, AA, and AS, homozygous deletion of CFHR3-1Δ (Pmeta = 3.2×10−7, OR = 1.47) conferred a higher risk of SLE than heterozygous deletion (Pmeta = 3.5×10−4, OR = 1.14). These results suggested that the CFHR3-1Δ deletion within the SLE-associated block, but not the previously described exonic SNPs of CFH, might contribute to the development of SLE in EA, AA, and AS, providing new insights into the role of complement regulators in the pathogenesis of SLE.
Author Summary
Systemic lupus erythematosus (SLE) is a complex autoimmune disease, associated with increased complement activation. Previous studies have provided evidence for the presence of SLE susceptibility gene(s) in the chromosome 1q31-32 locus. Within 1q32, genes encoding complement regulator factor H (CFH) and five CFH-related proteins (CFHR1-CFHR5) may contribute to the development of SLE, because genetic variants of these genes impair complement regulation and predispose to various human diseases. In this study, we tested association of genetic variants in the region containing CFH and CFHRs with SLE. We identified genetic variants predisposing to SLE in European American, African American, and Asian populations, which might be attributed to the deletion of CFHR3 and CFHR1 genes but not previously identified disease-associated exonic variants of CFH. This study provides the first evidence for consistent association between CFH/CFHRs and SLE across multi-ancestral SLE datasets, providing new insights into the role of complement regulators in the pathogenesis of SLE.
doi:10.1371/journal.pgen.1002079
PMCID: PMC3102741  PMID: 21637784
2.  ITGAM coding variant (rs1143679) influences the risk of renal disease, discoid rash, and immunologic manifestations in lupus patients with European ancestry 
Annals of the rheumatic diseases  2009;69(7):1329-1332.
Purpose
We hypothesized that the coding variant (R77H), rs1143679, within ITGAM could predict specific clinical manifestations associated with lupus.
Method
To assess genetic association, 2366 lupus cases and 2931 unaffected controls with European ancestry were analyzed. Lupus patients were coded by the presence or absence of individual ACR criteria. Logistic regression and Pearson chi-square tests were used to assess statistical significance.
Results
First, for overall case-control analysis, we detected highly significant (p=2.22×10−21, OR=1.73) association. Second, using case-only analysis we detected significant association with renal criteria (p=0.0003), discoid rash (p=0.02), and immunologic criteria (p=0.04). Third, we compared them with healthy controls, the association became stronger for renal (p=4.69×10−22, OR=2.15), discoid (p=1.77×10−14, OR=2.03), and immunologic (p=3.49×10−22, OR = 1.86) criteria. Risk allele frequency increased from 10.6% (controls) to 17.0% (lupus), 20.4% (renal), 18.1% (immunologic), and 19.5% (discoid).
Conclusion
These results demonstrated a strong association between the risk allele (A) at rs1143679 and renal disease, discoid rash, and immunological manifestations of lupus.
doi:10.1136/ard.2009.120543
PMCID: PMC2891778  PMID: 19939855
3.  Klinefelter’s Syndrome, 47,XXY, in Male Systemic Lupus Erythematosus Supports a Gene Dose Effect from the X Chromosome 
Arthritis and rheumatism  2008;58(8):2511-2517.
Background
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that predominantly affects women. Despite Klinefelter's syndrome (47,XXY) and SLE coexisting in isolated cases, no association has been established with SLE or any other autoimmune disease. Methods: Sex chromosome genotyping was performed in 981 SLE patients (213 were men). A first group of 843 SLE patients from 378 multiplex families and a second group of 138 men with non-familial SLE were evaluated. Fluorescent in situ hybridization (FISH) and karyotyping in transformed B cell lines enumerated chromosomes for selected cases.
Results
Of 213 men with SLE, five had Klinefelter's syndrome (or 1 in 43). Four of them were heterozygous at X markers. FISH and karyotyping confirmed Klinefelter’s syndrome in the fifth. An overall rate of 235 47,XXY per 10,000 male SLE patients (95%CI: 77 to 539) was found, a dramatic increase over the known prevalence of Klinefelter's syndrome in an unselected population (17 per 10,000 live male births). Asking men with SLE about fertility was highly sensitive (100%) for Klinefelter’s syndrome. All 768 SLE women were heterozygous at X.
Conclusions
47,XXY Klinefelter's syndrome, often subclinical, is increased in men with SLE by ~14-fold, compared to its prevalence in men without SLE. Diagnostic vigilance for 47,XXY males in SLE is warranted. These data are the first to associate Klinefelter's syndrome with an autoimmune disease found predominantly in women. The risk of SLE in Klinefelter's syndrome is predicted to be similar to the risk in normal 46,XX women and ~14-fold higher than in 46,XY men, consistent with SLE susceptibility being partly explained by a X chromosome gene dose effect.
doi:10.1002/art.23701
PMCID: PMC2824898  PMID: 18668569
4.  Prevalence of Osteoporosis and Osteopenia among African Americans with Early Rheumatoid Arthritis: The Impact of Ethnic-Specific Normative Data 
Purpose: To examine the prevalence of osteopenia and/or osteoporosis among African Americans with early rheumatoid arthritis (RA) and to assess the effect of using race/ethnicity-specific normative data.
Methods: Bone mineral density (BMD) of the hip and spine was assessed in African Americans with early RA. To examine the impact of using different normative data on disease classification, we calculated two sets of T scores, the first using sex-matched reference data from Caucasians and the second using data from African Americans. Osteoporosis was defined as a BMD at either site ≥2.5 SD below the young adult mean. Osteopenia was defined as a BMD ≥1 SD and <2.5 SD below this mean.
Results: Using Caucasian referent data, 33% (n=48) of patients had osteopenia or worse (n=48, 32.9%) and 5% (n=8) were osteoporotic. With the use of African-American normative data, 55% (n=94) were osteopenic or worse, and 16% (n=27) were osteoporotic.
Conclusion: African Americans with RA are at risk of osteopenia and/or osteoporosis. Different diagnostic classifications may occur in this population based solely on the normative data used for assessing fracture risk. These results underscore the need for a standardized approach in defining osteopenia and osteoporosis in African Americans.
PMCID: PMC1364462  PMID: 16173331
osteoporosis; osteopenia; African Americans; DXA; rheumatoid arthritis
5.  Prevalence of osteoporosis and osteopenia among African Americans with early rheumatoid arthritis: the impact of ethnic-specific normative data. 
PURPOSE: To examine the prevalence of osteopenia and/or osteoporosis among African Americans with early rheumatoid arthritis (RA) and to assess the effect of using race/ethnicity-specific normative data. METHODS: Bone mineral density (BMD) of the hip and spine was assessed in African Americans with early RA. To examine the impact of using different normative data on disease classification, we calculated two sets of T scores, the first using sex-matched reference data from Caucasians and the second using data from African Americans. Osteoporosis was defined as a BMD at either site > or =2.5 SD below the young adult mean. Osteopenia was defined as a BMD > or =1 SD and <2.5 SD below this mean. RESULTS: Using Caucasian referent data, 33% (n=48) of patients had osteopenia or worse (n=48, 32.9%) and 5% (n=8) were osteoporotic. With the use of African-American normative data, 55% (n=94) were osteopenic or worse, and 16% (n=27) were osteoporotic. CONCLUSION: African Americans with RA are at risk of osteopenia and/or osteoporosis. Different diagnostic classifications may occur in this population based solely on the normative data used for assessing fracture risk. These results underscore the need for a standardized approach in defining osteopenia and osteoporosis in African Americans.
PMCID: PMC1364462  PMID: 16173331

Results 1-5 (5)