Common Variants at 10 Genomic Loci Influence Hemoglobin A(1C) Levels via Glycemic and Nonglycemic Pathways

OBJECTIVE Glycated hemoglobin (HbA1c), used to monitor and diagnose diabetes, is influenced by average glycemia over a 2- to 3-month period. Genetic factors affecting expression, turnover, and abnormal glycation of hemoglobin could also be associated with increased levels of HbA1c. We aimed to identify such genetic factors and investigate the extent to which they influence diabetes classification based on HbA1c levels. RESEARCH DESIGN AND METHODS We studied associations with HbA1c in up to 46,368 nondiabetic adults of European descent from 23 genome-wide association studies (GWAS) and 8 cohorts with de novo genotyped single nucleotide polymorphisms (SNPs). We combined studies using inverse-variance meta-analysis and tested mediation by glycemia using conditional analyses. We estimated the global effect of HbA1c loci using a multilocus risk score, and used net reclassification to estimate genetic effects on diabetes screening. RESULTS Ten loci reached genome-wide significant association with HbA1c, including six new loci near FN3K (lead SNP/P value, rs1046896/P = 1.6 × 10−26), HFE (rs1800562/P = 2.6 × 10−20), TMPRSS6 (rs855791/P = 2.7 × 10−14), ANK1 (rs4737009/P = 6.1 × 10−12), SPTA1 (rs2779116/P = 2.8 × 10−9) and ATP11A/TUBGCP3 (rs7998202/P = 5.2 × 10−9), and four known HbA1c loci: HK1 (rs16926246/P = 3.1 × 10−54), MTNR1B (rs1387153/P = 4.0 × 10−11), GCK (rs1799884/P = 1.5 × 10−20) and G6PC2/ABCB11 (rs552976/P = 8.2 × 10−18). We show that associations with HbA1c are partly a function of hyperglycemia associated with 3 of the 10 loci (GCK, G6PC2 and MTNR1B). The seven nonglycemic loci accounted for a 0.19 (% HbA1c) difference between the extreme 10% tails of the risk score, and would reclassify ∼2% of a general white population screened for diabetes with HbA1c. CONCLUSIONS GWAS identified 10 genetic loci reproducibly associated with HbA1c. Six are novel and seven map to loci where rarer variants cause hereditary anemias and iron storage disorders. Common variants at these loci likely influence HbA1c levels via erythrocyte biology, and confer a small but detectable reclassification of diabetes diagnosis by HbA1c

Association of rs780094 in \u3ci\u3eGCKR\u3c/i\u3e with Metabolic Traits and Incident Diabetes and Cardiovascular Disease: The ARIC Study

Objective: The minor T-allele of rs780094 in the glucokinase regulator gene (GCKR) associates with a number of metabolic traits including higher triglyceride levels and improved glycemic regulation in study populations of mostly European ancestry. Using data from the Atherosclerosis Risk in Communities (ARIC) Study, we sought to replicate these findings, examine them in a large population-based sample of African American study participants, and to investigate independent associations with other metabolic traits in order to determine if variation in GKCR contributes to their observed clustering. In addition, we examined the association of rs780094 with incident diabetes, coronary heart disease (CHD), and stroke over up mean follow-up times of 8, 15, and 15 years, respectively. Research Design and Methods: Race-stratified analyses were conducted among 10,929 white and 3,960 black participants aged 45–64 at baseline assuming an additive genetic model and using linear and logistic regression and Cox proportional hazards models. Results: Previous findings replicated among white participants in multivariable adjusted models: the T-allele of rs780094 was associated with lower fasting glucose (p = 10-7) and insulin levels (p = 10-6), lower insulin resistance (HOMA-IR, p=10-9), less prevalent diabetes (p = 10-6), and higher CRP (p = 10-8), 2-h postprandial glucose (OGTT, p = 10-6), and triglyceride levels (p = 10-31). Moreover, the T-allele was independently associated with higher HDL cholesterol levels (p = 0.022), metabolic syndrome prevalence (p = 0.043), and lower beta-cell function measured as HOMA-B (p = 0.011). Among black participants, the T-allele was associated only with higher triglyceride levels (p = 0.004) and lower insulin levels (p = 0.002) and HOMA-IR (p = 0.013). Prospectively, the T-allele was associated with reduced incidence of diabetes (p = 10-4) among white participants, but not with incidence of CHD or stroke. Conclusions: Our findings indicate rs780094 has independent associations with multiple metabolic traits as well as incident diabetes, but not incident CHD or stroke. The magnitude of association between the SNP and most traits was of lower magnitude among African American compared to white participants

Genome-wide association and functional follow-up reveals new loci for kidney function

Chronic kidney disease (CKD) is an important public health problem with a genetic component. We performed genome-wide association studies in up to 130,600 European ancestry participants overall, and stratified for key CKD risk factors. We uncovered 6 new loci in association with estimated glomerular filtration rate (eGFR), the primary clinical measure of CKD, in or near MPPED2, DDX1, SLC47A1, CDK12, CASP9, and INO80. Morpholino knockdown of mpped2 and casp9 in zebrafish embryos revealed podocyte and tubular abnormalities with altered dextran clearance, suggesting a role for these genes in renal function. By providing new insights into genes that regulate renal function, these results could further our understanding of the pathogenesis of CKD

GWAS for executive function and processing speed suggests involvement of the CADM2 gene

To identify common variants contributing to normal variation in two specific domains of cognitive functioning, we conducted a genome-wide association study (GWAS) of executive functioning and information processing speed in non-demented older adults from the CHARGE (Cohorts for Heart and Aging Research in Genomic Epidemiology) consortium. Neuropsychological testing was available for 5429-32 070 subjects of European ancestry aged 45 years or older, free of dementia and clinical stroke at the time of cognitive testing from 20 cohorts in the discovery phase. We analyzed performance on the Trail Making Test parts A and B, the Letter Digit Substitution Test (LDST), the Digit Symbol Substitution Task (DSST), semantic and phonemic fluency tests, and the Stroop Color and Word Test. Replication was sought in 1311-21860 subjects from 20 independent cohorts. A significant association was observed in the discovery cohorts for the single-nucleotide polymorphism (SNP) rs17518584 (discovery P-value=3.12 × 10(-8)) and in the joint discovery and replication meta-analysis (P-value=3.28 × 10(-9) after adjustment for age, gender and education) in an intron of the gene cell adhesion molecule 2 (CADM2) for performance on the LDST/DSST. Rs17518584 is located about 170 kb upstream of the transcription start site of the major transcript for the CADM2 gene, but is within an intron of a variant transcript that includes an alternative first exon. The variant is associated with expression of CADM2 in the cingulate cortex (P-value=4 × 10(-4)). The protein encoded by CADM2 is involved in glutamate signaling (P-value=7.22 × 10(-15)), gamma-aminobutyric acid (GABA) transport (P-value=1.36 × 10(-11)) and neuron cell-cell adhesion (P-value=1.48 × 10(-13)). Our findings suggest that genetic variation in the CADM2 gene is associated with individual differences in information processing speed.Molecular Psychiatry advance online publication, 14 April 2015; doi:10.1038/mp.2015.37

Variants of GCKR Affect Both β-Cell and Kidney Function in Patients With Newly Diagnosed Type 2 Diabetes: The Verona Newly Diagnosed Type 2 Diabetes Study 2

In genome-wide association studies, performed mostly in nondiabetic individuals, genetic variability of glucokinase regulatory protein (GCKR) affects type 2 diabetes-relatedphenotypes, kidney function, and risk of chronic kidney disease (CKD). We tested whether GCKR variability affects type 2 diabetes or kidney-related phenotypes in newly diagnosed type 2diabetes. In 509 GAD-negative patients with newly diagnosedtype 2 diabetes,we 1) genotyped six single nucleotide polymorphisms in GCKR genomic region: rs6717980, rs1049817, rs6547626, rs780094, rs2384628, and rs8731; 2) assessedclinical phenotypes, insulin sensitivity by the euglycemic insulin clamp, and b-cell function by state-of-the-art modeling of glucose/C-peptide curves during an oral glucose tolerance test;and 3) estimated glomerular filtration rate (eGFR) by the Modification of Diet in Renal Disease formula.The major alleles of rs6717980 and rs2384628 were associated with reduced b-cell function (P<0.05), with mutual additive effects of each variant (P<0.01). The minoralleles of rs1049817 and rs6547626 and the major allele of rs780094 were associated withreduced eGFR according to a recessive model (P<0.03), but with no mutual additive effects of the variants. Additional associations were found between rs780094 and 2-h plasma glucose(P<0.05) and rs8731 and insulin sensitivity (P<0.05) and triglycerides (P<0.05). Our findings are compatible with the idea that GCKR variability may play a pathogenetic role in both type 2 diabetes and CKD. Genotyping GCKR in patients withnewly diagnosed type 2 diabetes might help in identifying patients at high risk for metabolic derangements or CKD

HbA1c as a risk factor for heart failure in persons with diabetes: the Atherosclerosis Risk in Communities (ARIC) study

Heart failure (HF) incidence in diabetes in both the presence and absence of CHD is rising. Prospective population-based studies can help describe the relationship between HbA1c, a measure of glycaemia control, and HF risk

Association of Estimated Glomerular Filtration Rate and Urinary Uromodulin Concentrations with Rare Variants Identified by UMOD Gene Region Sequencing

Background: Recent genome-wide association studies (GWAS) have identified common variants in the UMOD region associated with kidney function and disease in the general population. To identify novel rare variants as well as common variants that may account for this GWAS signal, the exons and 4 kb upstream region of UMOD were sequenced. Methodology/Principal Findings Individuals (n = 485) were selected based on presence of the GWAS risk haplotype and chronic kidney disease (CKD) in the ARIC Study and on the extremes of of the UMOD gene product, uromodulin, in urine (Tamm Horsfall protein, THP) in the Framingham Heart Study (FHS). Targeted sequencing was conducted using capillary based Sanger sequencing (3730 DNA Analyzer). Variants were tested for association with THP concentrations and estimated glomerular filtration rate (eGFR), and identified non-synonymous coding variants were genotyped in up to 22,546 follow-up samples. Twenty-four and 63 variants were identified in the 285 ARIC and 200 FHS participants, respectively. In both studies combined, there were 33 common and 54 rare (MAF<0.05) variants. Five non-synonymous rare variants were identified in FHS; borderline enrichment of rare variants was found in the extremes of THP (SKAT p-value = 0.08). Only V458L was associated with THP in the FHS general-population validation sample (p = 9*10$^{−3}$, n = 2,522), but did not show direction-consistent and significant association with eGFR in both the ARIC (n = 14,635) and FHS (n = 7,520) validation samples. Pooling all non-synonymous rare variants except V458L together showed non-significant associations with THP and eGFR in the FHS validation sample. Functional studies of V458L revealed no alternations in protein trafficking. Conclusions/Significance: Multiple novel rare variants in the UMOD region were identified, but none were consistently associated with eGFR in two independent study samples. Only V458L had modest association with THP levels in the general population and thus could not account for the observed GWAS signal

Transcription Factor 7-Like 2 (TCF7L2) Polymorphism and Context-Specific Risk of Type 2 Diabetes in African American and Caucasian Adults: The Atherosclerosis Risk in Communities Study

OBJECTIVE-Although variants in the transcription factor 7-like 2 (TCF7L2) gene are consistently associated with type 2 diabetes, large population-based studies of African Americans are lacking. Moreover, few studies have investigated the effects of TCF7L2 on type 2 diabetes in the context of metabolic risk factors of type 2 diabetes. RESEARCH DESIGN AND METHODS-We investigated the association between the TCF7L2 rs7903146 polymorphism and type 2 diabetes in 2,727 African American and 9,302 Caucasian participants without diabetes who were inducted into the Atherosclerosis Risk in Communities study in 1987-1989 and followed for 9 years. RESULTS-A total of 485 and 923 cases of type 2 diabetes were identified in African Americans and Caucasians, respectively. Compared with homozygous CC individuals, heterozygous CT and homozygous TT individuals had higher cumulative incidence of type 2 diabetes over 9 years of follow-up: 11.3% (95% CI 10.2-12.4) vs. 21.1% (20.8-21.4) and 27.9% (19.3-36.5) in African Americans, respectively, and 9.7% (8.8-10.6) vs. 11.3% (10.2-12.4) and 13.6% (11.1-16.1), respectively, in Caucasians. Individuals with the risk allele had the highest hazards of diabetes if they were obese and had low HDL cholesterol, followed by individuals with any one and none of the traits. CONCLUSIONS-Our study provides the first significant evidence of association between the TCF7L2 rs7903146 polymorphism and type 2 diabetes risk in a large African American population and also demonstrates that the diabetes risk conveyed by the rs7903146 risk allele is substantially increased in the context of some metabolic risk factors for type 2 diabetes. Our study findings need to be replicated in other large, population-based studies

Genetic polymorphisms located in genes related to immune and inflammatory processes are associated with end-stage renal disease: a preliminary study

Background Chronic kidney disease progression has been linked to pro-inflammatory cytokines and markers of inflammation. These markers are also elevated in end-stage renal disease (ESRD), which constitutes a serious public health problem. Objective To investigate whether single nucleotide polymorphisms (SNPs) located in genes related to immune and inflammatory processes, could be associated with ESRD development. Design and methods A retrospective case-control study was carried out on 276 patients with ESRD and 288 control subjects. Forty-eight SNPs were genotyped via SNPlex platform. Logistic regression was used to assess the relationship between each sigle polymorphism and the development of ESRD. Results Four polymorphisms showed association with ESRD: rs1801275 in the interleukin 4 receptor (IL4R) gene (OR: 0.66 (95%CI=0.46-0.95); p=0.025; overdominant model), rs4586 in chemokine (C-C motif) ligand 2 (CCL2) gene (OR: 0.70 (95%CI=0.54-0.90); p=0.005; additive model), rs301640 located in an intergenic binding site for signal transducer and activator of transcription 4 (STAT4) (OR: 1.82 (95%CI=1.17-2.83); p=0.006; additive model) and rs7830 in the nitric oxide synthase 3 (NOS3) gene (OR: 1.31 (95%CI=1.01-1.71); p=0.043; additive model). After adjusting for multiple testing, results lost significance. Conclusion Our preliminary data suggest that four genetic polymorphisms located in genes related to inflammation and immune processes could help to predict the risk of developing ESRD.This work was supported by grants from Instituto de Salud Carlos III (Ref: PI08/0738 and PI11/00245) to SR and Junta de Castilla y Leon (Ref: GRS 234/A/08) to ET. MAJS is supported by a grant from Instituto de Salud Carlos III (CM10/00105).Jimenez-Sousa, MA.; López, E.; Fernandez-Rodriguez, A.; Tamayo, E.; Fernández-Navarro, P.; Segura Roda, L.; Heredia, M.... (2012). Genetic polymorphisms located in genes related to immune and inflammatory processes are associated with end-stage renal disease: a preliminary study. BMC Medical Genetics. 13(58):1-6. https://doi.org/10.1186/1471-2350-13-58S161358Otero A, de Francisco A, Gayoso P, Garcia F: Prevalence of chronic renal disease in Spain: results of the EPIRCE study. Nefrologia. 2010, 30 (1): 78-86.Kottgen A: Genome-wide association studies in nephrology research. Am J Kidney Dis. 2010, 56 (4): 743-758. 10.1053/j.ajkd.2010.05.018.Gansevoort RT, Matsushita K, van der Velde M, Astor BC, Woodward M, Levey AS, Jong PE, Coresh J, de Jong PE, El-Nahas M, et al: Lower estimated GFR and higher albuminuria are associated with adverse kidney outcomes in both general and high-risk populations. A collaborative meta-analysis of general and high-risk population cohorts. Kidney Int. 2011, 80 (1): 93-104. 10.1038/ki.2010.531.Reich HN, Gladman DD, Urowitz MB, Bargman JM, Hladunewich MA, Lou W, Fan SC, Su J, Herzenberg AM, Cattran DC, et al: Persistent proteinuria and dyslipidemia increase the risk of progressive chronic kidney disease in lupus erythematosus. Kidney Int. 2011, 9 (8): 914-920.Rao M, Wong C, Kanetsky P, Girndt M, Stenvinkel P, Reilly M, Raj DS: Cytokine gene polymorphism and progression of renal and cardiovascular diseases. Kidney Int. 2007, 72 (5): 549-556. 10.1038/sj.ki.5002391.Munshi R, Hsu C, Himmelfarb J: Advances in understanding ischemic acute kidney injury. BMC Med. 2011, 9 (1): 11-10.1186/1741-7015-9-11.Kottgen A, Pattaro C, Boger CA, Fuchsberger C, Olden M, Glazer NL, Parsa A, Gao X, Yang Q, Smith AV, et al: New loci associated with kidney function and chronic kidney disease. Nat Genet. 2010, 42 (5): 376-384. 10.1038/ng.568.Chambers JC, Zhang W, Lord GM, van der Harst P, Lawlor DA, Sehmi JS, Gale DP, Wass MN, Ahmadi KR, Bakker SJ, et al: Genetic loci influencing kidney function and chronic kidney disease. Nat Genet. 2010, 42 (5): 373-375. 10.1038/ng.566.Ribases M, Ramos-Quiroga JA, Sanchez-Mora C, Bosch R, Richarte V, Palomar G, Gastaminza X, Bielsa A, Arcos-Burgos M, Muenke M, et al: Contribution of LPHN3 to the genetic susceptibility to ADHD in adulthood: a replication study. Genes Brain Behav. 2010, 10 (2): 149-157.Sole X, Guino E, Valls J, Iniesta R, Moreno V: SNPStats: a web tool for the analysis of association studies. Bioinformatics. 2006, 22 (15): 1928-1929. 10.1093/bioinformatics/btl268.Fried L, Solomon C, Shlipak M, Seliger S, Stehman-Breen C, Bleyer AJ, Chaves P, Furberg C, Kuller L, Newman A: Inflammatory and prothrombotic markers and the progression of renal disease in elderly individuals. J Am Soc Nephrol. 2004, 15 (12): 3184-3191. 10.1097/01.ASN.0000146422.45434.35.Wolkow PP, Niewczas MA, Perkins B, Ficociello LH, Lipinski B, Warram JH, Krolewski AS: Association of urinary inflammatory markers and renal decline in microalbuminuric type 1 diabetics. J Am Soc Nephrol. 2008, 19 (4): 789-797. 10.1681/ASN.2007050556.Nakamura E, Megumi Y, Kobayashi T, Kamoto T, Ishitoya S, Terachi T, Tachibana M, Matsushiro H, Habuchi T, Kakehi Y, et al: Genetic polymorphisms of the interleukin-4 receptor alpha gene are associated with an increasing risk and a poor prognosis of sporadic renal cell carcinoma in a Japanese population. Clin Cancer Res. 2002, 8 (8): 2620-2625.Burgos PI, Causey ZL, Tamhane A, Kelley JM, Brown EE, Hughes LB, Danila MI, van Everdingen A, Conn DL, Jonas BL, et al: Association of IL4R single-nucleotide polymorphisms with rheumatoid nodules in African Americans with rheumatoid arthritis. Arthritis Res Ther. 2010, 12 (3): R75-10.1186/ar2994.Tachdjian R, Mathias C, Al Khatib S, Bryce PJ, Kim HS, Blaeser F, O'Connor BD, Rzymkiewicz D, Chen A, Holtzman MJ, et al: Pathogenicity of a disease-associated human IL-4 receptor allele in experimental asthma. J Exp Med. 2009, 206 (10): 2191-2204. 10.1084/jem.20091480.Zheng G, Wang Y, Xiang SH, Tay YC, Wu H, Watson D, Coombes J, Rangan GK, Alexander SI, Harris DC: DNA vaccination with CCL2 DNA modified by the addition of an adjuvant epitope protects against "nonimmune" toxic renal injury. J Am Soc Nephrol. 2006, 17 (2): 465-474. 10.1681/ASN.2005020164.Kang YS, Lee MH, Song HK, Ko GJ, Kwon OS, Lim TK, Kim SH, Han SY, Han KH, Lee JE, et al: CCR2 antagonism improves insulin resistance, lipid metabolism, and diabetic nephropathy in type 2 diabetic mice. Kidney Int. 2010, 78 (9): 883-894. 10.1038/ki.2010.263.Dai R, Ahmed SA: MicroRNA, a new paradigm for understanding immunoregulation, inflammation, and autoimmune diseases. Transl Res. 2011, 157 (4): 163-179. 10.1016/j.trsl.2011.01.007.Messeguer X, Escudero R, Farre D, Nunez O, Martinez J, Alba MM: PROMO: detection of known transcription regulatory elements using species-tailored searches. Bioinformatics. 2002, 18 (2): 333-334. 10.1093/bioinformatics/18.2.333.Farre D, Roset R, Huerta M, Adsuara JE, Rosello L, Alba MM, Messeguer X: Identification of patterns in biological sequences at the ALGGEN server: PROMO and MALGEN. Nucleic Acids Res. 2003, 31 (13): 3651-3653. 10.1093/nar/gkg605.Wei L, Vahedi G, Sun HW, Watford WT, Takatori H, Ramos HL, Takahashi H, Liang J, Gutierrez-Cruz G, Zang C, et al: Discrete roles of STAT4 and STAT6 transcription factors in tuning epigenetic modifications and transcription during T helper cell differentiation. Immunity. 2010, 32 (6): 840-851. 10.1016/j.immuni.2010.06.003.Nakayama T, Sato W, Kosugi T, Zhang L, Campbell-Thompson M, Yoshimura A, Croker BP, Johnson RJ, Nakagawa T: Endothelial injury due to eNOS deficiency accelerates the progression of chronic renal disease in the mouse. Am J Physiol Renal Physiol. 2009, 296 (2): F317-327.Webber JL, Tooze SA: New insights into the function of Atg9. FEBS Lett. 2010, 584 (7): 1319-1326. 10.1016/j.febslet.2010.01.020.Kullo IJ, Greene MT, Boerwinkle E, Chu J, Turner ST, Kardia SL: Association of polymorphisms in NOS3 with the ankle-brachial index in hypertensive adults. Atherosclerosis. 2008, 196 (2): 905-912. 10.1016/j.atherosclerosis.2007.02.008.Popov AF, Hinz J, Schulz EG, Schmitto JD, Wiese CH, Quintel M, Seipelt R, Schoendube FA: The eNOS 786C/T polymorphism in cardiac surgical patients with cardiopulmonary bypass is associated with renal dysfunction. Eur J Cardiothorac Surg. 2009, 36 (4): 651-656. 10.1016/j.ejcts.2009.04.049.Wang CH, Li F, Hiller S, Kim HS, Maeda N, Smithies O, Takahashi N: A modest decrease in endothelial NOS in mice comparable to that associated with human NOS3 variants exacerbates diabetic nephropathy. Proc Natl Acad Sci U S A. 2011, 108 (5): 2070-2075. 10.1073/pnas.1018766108.Desmet FO, Hamroun D, Lalande M, Collod-Beroud G, Claustres M, Beroud C: Human Splicing Finder: an online bioinformatics tool to predict splicing signals. Nucleic Acids Res. 2009, 37 (9): e67-10.1093/nar/gkp215.Sironi M, Menozzi G, Riva L, Cagliani R, Comi GP, Bresolin N, Giorda R, Pozzoli U: Silencer elements as possible inhibitors of pseudoexon splicing. Nucleic Acids Res. 2004, 32 (5): 1783-1791. 10.1093/nar/gkh341.Perneger TV: What's wrong with Bonferroni adjustments. BMJ. 1998, 316 (7139): 1236-1238. 10.1136/bmj.316.7139.1236.Sterne JA, Davey Smith G: Sifting the evidence-what's wrong with significance tests?. BMJ. 2001, 322 (7280): 226-231. 10.1136/bmj.322.7280.226

Differential Effects of MYH9 and APOL1 Risk Variants on FRMD3 Association with Diabetic ESRD in African Americans

Single nucleotide polymorphisms (SNPs) in MYH9 and APOL1 on chromosome 22 (c22) are powerfully associated with non-diabetic end-stage renal disease (ESRD) in African Americans (AAs). Many AAs diagnosed with type 2 diabetic nephropathy (T2DN) have non-diabetic kidney disease, potentially masking detection of DN genes. Therefore, genome-wide association analyses were performed using the Affymetrix SNP Array 6.0 in 966 AA with T2DN and 1,032 non-diabetic, non-nephropathy (NDNN) controls, with and without adjustment for c22 nephropathy risk variants. No associations were seen between FRMD3 SNPs and T2DN before adjusting for c22 variants. However, logistic regression analysis revealed seven FRMD3 SNPs significantly interacting with MYH9—a finding replicated in 640 additional AA T2DN cases and 683 NDNN controls. Contrasting all 1,592 T2DN cases with all 1,671 NDNN controls, FRMD3 SNPs appeared to interact with the MYH9 E1 haplotype (e.g., rs942280 interaction p-value = 9.3E−7 additive; odds ratio [OR] 0.67). FRMD3 alleles were associated with increased risk of T2DN only in subjects lacking two MYH9 E1 risk haplotypes (rs942280 OR = 1.28), not in MYH9 E1 risk allele homozygotes (rs942280 OR = 0.80; homogeneity p-value = 4.3E−4). Effects were weaker stratifying on APOL1. FRMD3 SNPS were associated with T2DN, not type 2 diabetes per se, comparing AAs with T2DN to those with diabetes lacking nephropathy. T2DN-associated FRMD3 SNPs were detectable in AAs only after accounting for MYH9, with differential effects for APOL1. These analyses reveal a role for FRMD3 in AA T2DN susceptibility and accounting for c22 nephropathy risk variants can assist in detecting DN susceptibility genes