Background Elevated serum soluble E-selectin levels have been associated with a number of diseases. Although E-selectin levels are heritable, little is known about the specific genetic factors involved. E-selectin levels have been associated with the ABO blood group phenotype. Methods and Results We performed a high-resolution genome-wide association study of serum soluble E-selectin levels in 685 white individuals with type 1 diabetes from the Diabetes Control and Complications Trial (DCCT)/Epidemiology of Diabetes Intervention and Complications (EDIC) study to identify major loci influencing levels. Highly significant evidence for association (P=10−29) was observed for rs579459 near the ABO blood group gene, accounting for 19% of the variance in E-selectin levels. Levels of E-selectin were higher in O/O than O/A heterozygotes, which were likewise higher than A/A genotypes. Analysis of subgroups of A alleles reveals heterogeneity in the association, and even after this was accounted for, an intron 1 SNP remained significantly associated. We replicate the ABO association in nondiabetic individuals. Conclusion ABO is a major locus for serum soluble E-selectin levels. We excluded population stratification, fine-mapped the association to sub-A alleles, and also document association with additional variation in the ABO region.

OBJECTIVEGlycemia is a major risk factor for the development of long-term complications in type 1 diabetes; however, no specific genetic loci have been identified for glycemic control in individuals with type 1 diabetes. To identify such loci in type 1 diabetes, we analyzed longitudinal repeated measures of A1C from the Diabetes Control and Complications Trial.RESEARCH DESIGN AND METHODSWe performed a genome-wide association study using the mean of quarterly A1C values measured over 6.5 years, separately in the conventional (n = 667) and intensive (n = 637) treatment groups of the DCCT. At loci of interest, linear mixed models were used to take advantage of all the repeated measures. We then assessed the association of these loci with capillary glucose and repeated measures of multiple complications of diabetes.RESULTSWe identified a major locus for A1C levels in the conventional treatment group near SORCS1 (10q25.1, P = 7 × 10−10), which was also associated with mean glucose (P = 2 × 10−5). This was confirmed using A1C in the intensive treatment group (P = 0.01). Other loci achieved evidence close to genome-wide significance: 14q32.13 (GSC) and 9p22 (BNC2) in the combined treatment groups and 15q21.3 (WDR72) in the intensive group. Further, these loci gave evidence for association with diabetic complications, specifically SORCS1 with hypoglycemia and BNC2 with renal and retinal complications. We replicated the SORCS1 association in Genetics of Diabetes in Kidneys (GoKinD) study control subjects (P = 0.01) and the BNC2 association with A1C in nondiabetic individuals.CONCLUSIONSA major locus for A1C and glucose in individuals with diabetes is near SORCS1. This may influence the design and analysis of genetic studies attempting to identify risk factors for long-term diabetic complications.

Quebec platelet disorder (QPD) is an autosomal dominant bleeding disorder linked to a region on chromosome 10 that includes PLAU, the urokinase plasminogen activator gene. QPD increases urokinase plasminogen activator mRNA levels, particularly during megakaryocyte differentiation, without altering expression of flanking genes. Because PLAU sequence changes were excluded as the cause of this bleeding disorder, we investigated whether the QPD mutation involved PLAU copy number variation. All 38 subjects with QPD had a direct tandem duplication of a 78-kb genomic segment that includes PLAU. This mutation was specific to QPD as it was not present in any unaffected family members (n ‫؍‬ 114), unrelated French Canadians (n ‫؍‬ 221), or other persons tested (n ‫؍‬ 90). This new information on the genetic mutation will facilitate diagnostic testing for QPD and studies of its pathogenesis and prevalence. QPD is the first bleeding disorder to be associated with a gene duplication event and a PLAU mutation. (Blood. 2010;115: 1264-1266)

The androgen receptor (AR) is a transcription factor mediating the action of androgens. The AR gene is localized on chromosome X and it contains a series of CAG trinucleotide repeats. The length of the CAG repeats varies among individuals and this polymorphism is believed to be related to AR transcriptional activity. Studies have shown that fewer CAG repeats are associated with an increased risk as well as more aggressive forms of prostate cancer. Although AR is expressed in breast cancer and the impact of androgen and AR on breast cancer has been recognized, the role of the CAG repeats in breast cancer remains unknown. In this study, we measured the CAG repeats in breast cancer tissue using a PCR-based method. Of the 133 patients with primary breast cancer, 102 were heterozygous and 31 were homozygous. The mean CAG repeat number for homozygous women was 21; for heterozygous women the repeat number mean was 20 for the short allele and 24 for the long allele. The length of CAG repeats either in one allele or in both alleles was inversely correlated with the histological grade of breast cancer (r = -0.23 or -0.26, respectively, p < 0.05). An association between positive lymph nodes and fewer CAG repeats in both alleles was also suggested (p = 0.06). Furthermore, survival analysis indicated that the total number of CAG repeats in both alleles was associated with patient overall survival. With every CAG repeat increase, there was a 6% reduction in the risk of death (RR = 0.94, p = 0.03). The association remained significant after controlling for the homozygous and heterozygous status (RR = 0.92, p = 0.01). The association became no longer significant when clinical and pathological variables were adjusted in the analysis but this could be due to the reduction of sample size in the multivariate analysis. CAG heterozygosity and difference in number of CAG repeats between the two alleles were not associated with either disease features or patient survival. Our results suggest that longer CAG repeats may occur more frequently in less aggressive cancer and that the CAG repeats may play a role in breast cancer progression.

BACKGROUND— Despite familial clustering of nephropathy and retinopathy severity in type 1 diabetes, few gene variants have been consistently associated with these outcomes. RESEARCH DESIGN AND METHODS— We performed an individual-based genetic association study with time to renal and retinal outcomes in 1,362 white probands with type 1 diabetes from the Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications (DCCT/EDIC) study. Specifically, we genotyped 1,411 SNPs that capture common variations in 212 candidate genes for long-term complications and analyzed them for association with the time from DCCT baseline to event for renal and retinal outcomes using multivariate Cox proportion hazards models. To address multiple testing and assist interpretation of the results, false discovery rate q values were calculated separately for each outcome. RESULTS— We observed association between rs17880135 in the 3′ region of superoxide dismutase 1 (SOD1) and the incidence of both severe nephropathy (hazard ratio [HR] 2.62 [95% CI 1.64–4.18], P = 5.6 × 10−5, q = 0.06) and persistent microalbuminuria (1.82 [1.29–2.57], P = 6.4 × 10−4, q = 0.46). Sequencing and fine-mapping identified additional SOD1 variants, including rs202446, rs9974610, and rs204732, which were also associated (P &lt; 10−3) with persistent microalbuminuria, whereas rs17880135 and rs17881180 were similarly associated with the development of severe nephropathy. Attempts to replicate the findings in three cross-sectional case-control studies produced equivocal results. We observed no striking differences between risk genotypes in serum SOD activity, serum SOD1 mass, or SOD1 mRNA expression in lymphoblastoid cell lines. CONCLUSIONS— Multiple variations in SOD1 are significantly associated with persistent microalbuminuria and severe nephropathy in the DCCT/EDIC study.