@article {1154, title = {Common coding variants of the HNF1A gene are associated with multiple cardiovascular risk phenotypes in community-based samples of younger and older European-American adults: the Coronary Artery Risk Development in Young Adults Study and The Cardiovascula}, journal = {Circ Cardiovasc Genet}, volume = {2}, year = {2009}, month = {2009 Jun}, pages = {244-54}, abstract = {

BACKGROUND: The transcription factor hepatocyte nuclear factor (HNF)-1 alpha regulates the activity of a number of genes involved in innate immunity, blood coagulation, lipid and glucose transport and metabolism, and cellular detoxification. Common polymorphisms of the HNF-1 alpha gene (HNF1A) were recently associated with plasma C-reactive protein and gamma-glutamyl transferase concentration in middle-aged to older European Americans (EA).

METHODS AND RESULTS: We assessed whether common variants of HNF1A are associated with C-reactive protein, gamma-glutamyl transferase, and other atherosclerotic and metabolic risk factors, in the large, population-based Coronary Artery Risk Development in Young Adults Study of healthy young EA (n=2154) and African American (AA; n=2083) adults. The minor alleles of Ile27Leu (rs1169288) and Ser486Asn (rs2464196) were associated with 0.10 to 0.15 standard deviation units lower C-reactive protein and gamma-glutamyl transferase levels in EA. The same HNF1A coding variants were associated with higher low-density lipoprotein cholesterol, apolipoprotein B, creatinine, and fibrinogen in EA. We replicated the associations between HNF1A coding variants and C-reactive protein, fibrinogen, low-density lipoprotein cholesterol, and renal function in a second population-based sample of EA adults 65 years and older from the Cardiovascular Health Study. The HNF1A Ser486Asn and/or Ile27Leu variants were also associated with increased risk of subclinical coronary atherosclerosis in Coronary Artery Risk Development in Young Adults and with incident coronary heart disease in Cardiovascular Health Study. The Ile27Leu and Ser486Asn variants were 3-fold less common in AA than in EA. There was little evidence of association between HNF1A genotype and atherosclerosis-related phenotypes in AA.

CONCLUSIONS: Common polymorphisms of HNF1A seem to influence multiple phenotypes related to cardiovascular risk in the general population of younger and older EA adults.

}, keywords = {Adolescent, Adult, African Americans, Aged, Aged, 80 and over, C-Reactive Protein, Cardiovascular Diseases, Cholesterol, LDL, Cohort Studies, European Continental Ancestry Group, Female, Fibrinogen, gamma-Glutamyltransferase, Genetic Predisposition to Disease, Genotype, Hepatocyte Nuclear Factor 1-alpha, Humans, Male, Middle Aged, Phenotype, Polymorphism, Single Nucleotide, Risk Factors}, issn = {1942-3268}, doi = {10.1161/CIRCGENETICS.108.839506}, author = {Reiner, Alexander P and Gross, Myron D and Carlson, Christopher S and Bielinski, Suzette J and Lange, Leslie A and Fornage, Myriam and Jenny, Nancy S and Walston, Jeremy and Tracy, Russell P and Williams, O Dale and Jacobs, David R and Nickerson, Deborah A} } @article {6065, title = {Effects of smoking on the genetic risk of obesity: the population architecture using genomics and epidemiology study.}, journal = {BMC Med Genet}, volume = {14}, year = {2013}, month = {2013 Jan 11}, pages = {6}, abstract = {

BACKGROUND: Although smoking behavior is known to affect body mass index (BMI), the potential for smoking to influence genetic associations with BMI is largely unexplored.

METHODS: As part of the {\textquoteright}Population Architecture using Genomics and Epidemiology (PAGE){\textquoteright} Consortium, we investigated interaction between genetic risk factors associated with BMI and smoking for 10 single nucleotide polymorphisms (SNPs) previously identified in genome-wide association studies. We included 6 studies with a total of 56,466 subjects (16,750 African Americans (AA) and 39,716 European Americans (EA)). We assessed effect modification by testing an interaction term for each SNP and smoking (current vs. former/never) in the linear regression and by stratified analyses.

RESULTS: We did not observe strong evidence for interactions and only observed two interactions with p-values <0.1: for rs6548238/TMEM18, the risk allele (C) was associated with BMI only among AA females who were former/never smokers (β = 0.018, p = 0.002), vs. current smokers (β = 0.001, p = 0.95, p(interaction) = 0.10). For rs9939609/FTO, the A allele was more strongly associated with BMI among current smoker EA females (β = 0.017, p = 3.5 x 10(-5)), vs. former/never smokers (β = 0.006, p = 0.05, p(interaction) = 0.08).

CONCLUSIONS: These analyses provide limited evidence that smoking status may modify genetic effects of previously identified genetic risk factors for BMI. Larger studies are needed to follow up our results.

CLINICAL TRIAL REGISTRATION: NCT00000611.

}, keywords = {Adolescent, Adult, African Americans, Aged, Alpha-Ketoglutarate-Dependent Dioxygenase FTO, Body Mass Index, European Continental Ancestry Group, Female, Genetic Predisposition to Disease, Humans, Male, Membrane Proteins, Middle Aged, Obesity, Polymorphism, Single Nucleotide, Proteins, Risk Factors, Smoking, Young Adult}, issn = {1471-2350}, doi = {10.1186/1471-2350-14-6}, author = {Fesinmeyer, Megan D and North, Kari E and Lim, Unhee and B{\r u}zkov{\'a}, Petra and Crawford, Dana C and Haessler, Jeffrey and Gross, Myron D and Fowke, Jay H and Goodloe, Robert and Love, Shelley-Ann and Graff, Misa and Carlson, Christopher S and Kuller, Lewis H and Matise, Tara C and Hong, Ching-Ping and Henderson, Brian E and Allen, Melissa and Rohde, Rebecca R and Mayo, Ping and Schnetz-Boutaud, Nathalie and Monroe, Kristine R and Ritchie, Marylyn D and Prentice, Ross L and Kolonel, Lawrence N and Manson, JoAnn E and Pankow, James and Hindorff, Lucia A and Franceschini, Nora and Wilkens, Lynne R and Haiman, Christopher A and Le Marchand, Lo{\"\i}c and Peters, Ulrike} } @article {6631, title = {Genetic risk factors for BMI and obesity in an ethnically diverse population: results from the population architecture using genomics and epidemiology (PAGE) study.}, journal = {Obesity (Silver Spring)}, volume = {21}, year = {2013}, month = {2013 Apr}, pages = {835-46}, abstract = {

OBJECTIVE: Several genome-wide association studies (GWAS) have demonstrated that common genetic variants contribute to obesity. However, studies of this complex trait have focused on ancestrally European populations, despite the high prevalence of obesity in some minority groups.

DESIGN AND METHODS: As part of the "Population Architecture using Genomics and Epidemiology (PAGE)" Consortium, we investigated the association between 13 GWAS-identified single-nucleotide polymorphisms (SNPs) and BMI and obesity in 69,775 subjects, including 6,149 American Indians, 15,415 African-Americans, 2,438 East Asians, 7,346 Hispanics, 604 Pacific Islanders, and 37,823 European Americans. For the BMI-increasing allele of each SNP, we calculated β coefficients using linear regression (for BMI) and risk estimates using logistic regression (for obesity defined as BMI >= 30) followed by fixed-effects meta-analysis to combine results across PAGE sites. Analyses stratified by racial/ethnic group assumed an additive genetic model and were adjusted for age, sex, and current smoking. We defined "replicating SNPs" (in European Americans) and "generalizing SNPs" (in other racial/ethnic groups) as those associated with an allele frequency-specific increase in BMI.

RESULTS: By this definition, we replicated 9/13 SNP associations (5 out of 8 loci) in European Americans. We also generalized 8/13 SNP associations (5/8 loci) in East Asians, 7/13 (5/8 loci) in African Americans, 6/13 (4/8 loci) in Hispanics, 5/8 in Pacific Islanders (5/8 loci), and 5/9 (4/8 loci) in American Indians.

CONCLUSION: Linkage disequilibrium patterns suggest that tagSNPs selected for European Americans may not adequately tag causal variants in other ancestry groups. Accordingly, fine-mapping in large samples is needed to comprehensively explore these loci in diverse populations.

}, keywords = {Alleles, Body Mass Index, Ethnic Groups, Gene Frequency, Genetic Loci, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Linkage Disequilibrium, Metagenomics, Obesity, Phenotype, Polymorphism, Single Nucleotide, Risk Factors}, issn = {1930-739X}, doi = {10.1002/oby.20268}, author = {Fesinmeyer, Megan D and North, Kari E and Ritchie, Marylyn D and Lim, Unhee and Franceschini, Nora and Wilkens, Lynne R and Gross, Myron D and B{\r u}zkov{\'a}, Petra and Glenn, Kimberly and Quibrera, P Miguel and Fernandez-Rhodes, Lindsay and Li, Qiong and Fowke, Jay H and Li, Rongling and Carlson, Christopher S and Prentice, Ross L and Kuller, Lewis H and Manson, JoAnn E and Matise, Tara C and Cole, Shelley A and Chen, Christina T L and Howard, Barbara V and Kolonel, Laurence N and Henderson, Brian E and Monroe, Kristine R and Crawford, Dana C and Hindorff, Lucia A and Buyske, Steven and Haiman, Christopher A and Le Marchand, Lo{\"\i}c and Peters, Ulrike} } @article {6282, title = {Genome-wide and gene-centric analyses of circulating myeloperoxidase levels in the charge and care consortia.}, journal = {Hum Mol Genet}, volume = {22}, year = {2013}, month = {2013 Aug 15}, pages = {3381-93}, abstract = {

Increased systemic levels of myeloperoxidase (MPO) are associated with the risk of coronary artery disease (CAD). To identify the genetic factors that are associated with circulating MPO levels, we carried out a genome-wide association study (GWAS) and a gene-centric analysis in subjects of European ancestry and African Americans (AAs). A locus on chromosome 1q31.1 containing the complement factor H (CFH) gene was strongly associated with serum MPO levels in 9305 subjects of European ancestry (lead SNP rs800292; P = 4.89 {\texttimes} 10(-41)) and in 1690 AA subjects (rs505102; P = 1.05 {\texttimes} 10(-8)). Gene-centric analyses in 8335 subjects of European ancestry additionally identified two rare MPO coding sequence variants that were associated with serum MPO levels (rs28730837, P = 5.21 {\texttimes} 10(-12); rs35897051, P = 3.32 {\texttimes} 10(-8)). A GWAS for plasma MPO levels in 9260 European ancestry subjects identified a chromosome 17q22 region near MPO that was significantly associated (lead SNP rs6503905; P = 2.94 {\texttimes} 10(-12)), but the CFH locus did not exhibit evidence of association with plasma MPO levels. Functional analyses revealed that rs800292 was associated with levels of complement proteins in serum. Variants at chromosome 17q22 also had pleiotropic cis effects on gene expression. In a case-control analysis of \~{}80 000 subjects from CARDIoGRAM, none of the identified single-nucleotide polymorphisms (SNPs) were associated with CAD. These results suggest that distinct genetic factors regulate serum and plasma MPO levels, which may have relevance for various acute and chronic inflammatory disorders. The clinical implications for CAD and a better understanding of the functional basis for the association of CFH and MPO variants with circulating MPO levels require further study.

}, keywords = {Adult, African Americans, Aged, Case-Control Studies, Complement Factor H, Coronary Artery Disease, European Continental Ancestry Group, Female, Gene Expression Regulation, Enzymologic, Genetic Association Studies, Genetic Variation, Genome-Wide Association Study, Genotype, Humans, Male, Middle Aged, Peroxidase, Polymorphism, Single Nucleotide, Young Adult}, issn = {1460-2083}, doi = {10.1093/hmg/ddt189}, author = {Reiner, Alexander P and Hartiala, Jaana and Zeller, Tanja and Bis, Joshua C and Dupuis, Jos{\'e}e and Fornage, Myriam and Baumert, Jens and Kleber, Marcus E and Wild, Philipp S and Baldus, Stephan and Bielinski, Suzette J and Fontes, Jo{\~a}o D and Illig, Thomas and Keating, Brendan J and Lange, Leslie A and Ojeda, Francisco and M{\"u}ller-Nurasyid, Martina and Munzel, Thomas F and Psaty, Bruce M and Rice, Kenneth and Rotter, Jerome I and Schnabel, Renate B and Tang, W H Wilson and Thorand, Barbara and Erdmann, Jeanette and Jacobs, David R and Wilson, James G and Koenig, Wolfgang and Tracy, Russell P and Blankenberg, Stefan and M{\"a}rz, Winfried and Gross, Myron D and Benjamin, Emelia J and Hazen, Stanley L and Allayee, Hooman} } @article {6630, title = {The influence of obesity-related single nucleotide polymorphisms on BMI across the life course: the PAGE study.}, journal = {Diabetes}, volume = {62}, year = {2013}, month = {2013 May}, pages = {1763-7}, abstract = {

Evidence is limited as to whether heritable risk of obesity varies throughout adulthood. Among >34,000 European Americans, aged 18-100 years, from multiple U.S. studies in the Population Architecture using Genomics and Epidemiology (PAGE) Consortium, we examined evidence for heterogeneity in the associations of five established obesity risk variants (near FTO, GNPDA2, MTCH2, TMEM18, and NEGR1) with BMI across four distinct epochs of adulthood: 1) young adulthood (ages 18-25 years), adulthood (ages 26-49 years), middle-age adulthood (ages 50-69 years), and older adulthood (ages >=70 years); or 2) by menopausal status in women and stratification by age 50 years in men. Summary-effect estimates from each meta-analysis were compared for heterogeneity across the life epochs. We found heterogeneity in the association of the FTO (rs8050136) variant with BMI across the four adulthood epochs (P = 0.0006), with larger effects in young adults relative to older adults (β [SE] = 1.17 [0.45] vs. 0.09 [0.09] kg/m{\texttwosuperior}, respectively, per A allele) and smaller intermediate effects. We found no evidence for heterogeneity in the association of GNPDA2, MTCH2, TMEM18, and NEGR1 with BMI across adulthood. Genetic predisposition to obesity may have greater effects on body weight in young compared with older adulthood for FTO, suggesting changes by age, generation, or secular trends. Future research should compare and contrast our findings with results using longitudinal data.

}, keywords = {Adolescent, Adult, Aged, Aged, 80 and over, Aging, Body Mass Index, Cohort Studies, Cross-Sectional Studies, European Continental Ancestry Group, Female, Genetic Association Studies, Health Surveys, Humans, Male, Middle Aged, Obesity, Polymorphism, Single Nucleotide, Proteins, United States, Young Adult}, issn = {1939-327X}, doi = {10.2337/db12-0863}, author = {Graff, Mariaelisa and Gordon-Larsen, Penny and Lim, Unhee and Fowke, Jay H and Love, Shelly-Ann and Fesinmeyer, Megan and Wilkens, Lynne R and Vertilus, Shawyntee and Ritchie, Marilyn D and Prentice, Ross L and Pankow, Jim and Monroe, Kristine and Manson, JoAnn E and Le Marchand, Lo{\"\i}c and Kuller, Lewis H and Kolonel, Laurence N and Hong, Ching P and Henderson, Brian E and Haessler, Jeff and Gross, Myron D and Goodloe, Robert and Franceschini, Nora and Carlson, Christopher S and Buyske, Steven and B{\r u}zkov{\'a}, Petra and Hindorff, Lucia A and Matise, Tara C and Crawford, Dana C and Haiman, Christopher A and Peters, Ulrike and North, Kari E} } @article {6558, title = {Large multiethnic Candidate Gene Study for C-reactive protein levels: identification of a novel association at CD36 in African Americans.}, journal = {Hum Genet}, volume = {133}, year = {2014}, month = {2014 Aug}, pages = {985-95}, abstract = {

C-reactive protein (CRP) is a heritable biomarker of systemic inflammation and a predictor of cardiovascular disease (CVD). Large-scale genetic association studies for CRP have largely focused on individuals of European descent. We sought to uncover novel genetic variants for CRP in a multiethnic sample using the ITMAT Broad-CARe (IBC) array, a custom 50,000 SNP gene-centric array having dense coverage of over 2,000 candidate CVD genes. We performed analyses on 7,570 African Americans (AA) from the Candidate gene Association Resource (CARe) study and race-combined meta-analyses that included 29,939 additional individuals of European descent from CARe, the Women{\textquoteright}s Health Initiative (WHI) and KORA studies. We observed array-wide significance (p < 2.2 {\texttimes} 10(-6)) for four loci in AA, three of which have been reported previously in individuals of European descent (IL6R, p = 2.0 {\texttimes} 10(-6); CRP, p = 4.2 {\texttimes} 10(-71); APOE, p = 1.6 {\texttimes} 10(-6)). The fourth significant locus, CD36 (p = 1.6 {\texttimes} 10(-6)), was observed at a functional variant (rs3211938) that is extremely rare in individuals of European descent. We replicated the CD36 finding (p = 1.8 {\texttimes} 10(-5)) in an independent sample of 8,041 AA women from WHI; a meta-analysis combining the CARe and WHI AA results at rs3211938 reached genome-wide significance (p = 1.5 {\texttimes} 10(-10)). In the race-combined meta-analyses, 13 loci reached significance, including ten (CRP, TOMM40/APOE/APOC1, HNF1A, LEPR, GCKR, IL6R, IL1RN, NLRP3, HNF4A and BAZ1B/BCL7B) previously associated with CRP, and one (ARNTL) previously reported to be nominally associated with CRP. Two novel loci were also detected (RPS6KB1, p = 2.0 {\texttimes} 10(-6); CD36, p = 1.4 {\texttimes} 10(-6)). These results highlight both shared and unique genetic risk factors for CRP in AA compared to populations of European descent.

}, keywords = {Adult, African Americans, Aged, Biomarkers, C-Reactive Protein, Cardiovascular Diseases, CD36 Antigens, Female, Genetic Loci, Genetic Predisposition to Disease, Genetics, Population, Genome-Wide Association Study, Humans, Meta-Analysis as Topic, Middle Aged, Polymorphism, Single Nucleotide, Risk Factors}, issn = {1432-1203}, doi = {10.1007/s00439-014-1439-z}, author = {Ellis, Jaclyn and Lange, Ethan M and Li, Jin and Dupuis, Jos{\'e}e and Baumert, Jens and Walston, Jeremy D and Keating, Brendan J and Durda, Peter and Fox, Ervin R and Palmer, Cameron D and Meng, Yan A and Young, Taylor and Farlow, Deborah N and Schnabel, Renate B and Marzi, Carola S and Larkin, Emma and Martin, Lisa W and Bis, Joshua C and Auer, Paul and Ramachandran, Vasan S and Gabriel, Stacey B and Willis, Monte S and Pankow, James S and Papanicolaou, George J and Rotter, Jerome I and Ballantyne, Christie M and Gross, Myron D and Lettre, Guillaume and Wilson, James G and Peters, Ulrike and Koenig, Wolfgang and Tracy, Russell P and Redline, Susan and Reiner, Alex P and Benjamin, Emelia J and Lange, Leslie A} } @article {6597, title = {Association of exome sequences with plasma C-reactive protein levels in >9000 participants.}, journal = {Hum Mol Genet}, volume = {24}, year = {2015}, month = {2015 Jan 15}, pages = {559-71}, abstract = {

C-reactive protein (CRP) concentration is a heritable systemic marker of inflammation that is associated with cardiovascular disease risk. Genome-wide association studies have identified CRP-associated common variants associated in \~{}25 genes. Our aims were to apply exome sequencing to (1) assess whether the candidate loci contain rare coding variants associated with CRP levels and (2) perform an exome-wide search for rare variants in novel genes associated with CRP levels. We exome-sequenced 6050 European-Americans (EAs) and 3109 African-Americans (AAs) from the NHLBI-ESP and the CHARGE consortia, and performed association tests of sequence data with measured CRP levels. In single-variant tests across candidate loci, a novel rare (minor allele frequency = 0.16\%) CRP-coding variant (rs77832441-A; p.Thr59Met) was associated with 53\% lower mean CRP levels (P = 2.9 {\texttimes} 10(-6)). We replicated the association of rs77832441 in an exome array analysis of 11 414 EAs (P = 3.0 {\texttimes} 10(-15)). Despite a strong effect on CRP levels, rs77832441 was not associated with inflammation-related phenotypes including coronary heart disease. We also found evidence for an AA-specific association of APOE-ε2 rs7214 with higher CRP levels. At the exome-wide significance level (P < 5.0 {\texttimes} 10(-8)), we confirmed associations for reported common variants of HNF1A, CRP, IL6R and TOMM40-APOE. In gene-based tests, a burden of rare/lower frequency variation in CRP in EAs (P <= 6.8 {\texttimes} 10(-4)) and in retinoic acid receptor-related orphan receptor α (RORA) in AAs (P = 1.7 {\texttimes} 10(-3)) were associated with CRP levels at the candidate gene level (P < 2.0 {\texttimes} 10(-3)). This inquiry did not elucidate novel genes, but instead demonstrated that variants distributed across the allele frequency spectrum within candidate genes contribute to CRP levels.

}, keywords = {Adult, African Americans, C-Reactive Protein, Cardiovascular Diseases, Cohort Studies, European Continental Ancestry Group, Exome, Female, Gene Frequency, Genetic Predisposition to Disease, Genome-Wide Association Study, Hepatocyte Nuclear Factor 1-alpha, Humans, Male, Plasma, Polymorphism, Single Nucleotide, Receptors, Interleukin-6, Risk Factors}, issn = {1460-2083}, doi = {10.1093/hmg/ddu450}, author = {Schick, Ursula M and Auer, Paul L and Bis, Joshua C and Lin, Honghuang and Wei, Peng and Pankratz, Nathan and Lange, Leslie A and Brody, Jennifer and Stitziel, Nathan O and Kim, Daniel S and Carlson, Christopher S and Fornage, Myriam and Haessler, Jeffery and Hsu, Li and Jackson, Rebecca D and Kooperberg, Charles and Leal, Suzanne M and Psaty, Bruce M and Boerwinkle, Eric and Tracy, Russell and Ardissino, Diego and Shah, Svati and Willer, Cristen and Loos, Ruth and Melander, Olle and McPherson, Ruth and Hovingh, Kees and Reilly, Muredach and Watkins, Hugh and Girelli, Domenico and Fontanillas, Pierre and Chasman, Daniel I and Gabriel, Stacey B and Gibbs, Richard and Nickerson, Deborah A and Kathiresan, Sekar and Peters, Ulrike and Dupuis, Jos{\'e}e and Wilson, James G and Rich, Stephen S and Morrison, Alanna C and Benjamin, Emelia J and Gross, Myron D and Reiner, Alex P} } @article {7596, title = {Impact of common genetic determinants of Hemoglobin A1c on type 2 diabetes risk and diagnosis in ancestrally diverse populations: A transethnic genome-wide meta-analysis.}, journal = {PLoS Med}, volume = {14}, year = {2017}, month = {2017 Sep}, pages = {e1002383}, abstract = {

BACKGROUND: Glycated hemoglobin (HbA1c) is used to diagnose type 2 diabetes (T2D) and assess glycemic control in patients with diabetes. Previous genome-wide association studies (GWAS) have identified 18 HbA1c-associated genetic variants. These variants proved to be classifiable by their likely biological action as erythrocytic (also associated with erythrocyte traits) or glycemic (associated with other glucose-related traits). In this study, we tested the hypotheses that, in a very large scale GWAS, we would identify more genetic variants associated with HbA1c and that HbA1c variants implicated in erythrocytic biology would affect the diagnostic accuracy of HbA1c. We therefore expanded the number of HbA1c-associated loci and tested the effect of genetic risk-scores comprised of erythrocytic or glycemic variants on incident diabetes prediction and on prevalent diabetes screening performance. Throughout this multiancestry study, we kept a focus on interancestry differences in HbA1c genetics performance that might influence race-ancestry differences in health outcomes.

METHODS \& FINDINGS: Using genome-wide association meta-analyses in up to 159,940 individuals from 82 cohorts of European, African, East Asian, and South Asian ancestry, we identified 60 common genetic variants associated with HbA1c. We classified variants as implicated in glycemic, erythrocytic, or unclassified biology and tested whether additive genetic scores of erythrocytic variants (GS-E) or glycemic variants (GS-G) were associated with higher T2D incidence in multiethnic longitudinal cohorts (N = 33,241). Nineteen glycemic and 22 erythrocytic variants were associated with HbA1c at genome-wide significance. GS-G was associated with higher T2D risk (incidence OR = 1.05, 95\% CI 1.04-1.06, per HbA1c-raising allele, p = 3 {\texttimes} 10-29); whereas GS-E was not (OR = 1.00, 95\% CI 0.99-1.01, p = 0.60). In Europeans and Asians, erythrocytic variants in aggregate had only modest effects on the diagnostic accuracy of HbA1c. Yet, in African Americans, the X-linked G6PD G202A variant (T-allele frequency 11\%) was associated with an absolute decrease in HbA1c of 0.81\%-units (95\% CI 0.66-0.96) per allele in hemizygous men, and 0.68\%-units (95\% CI 0.38-0.97) in homozygous women. The G6PD variant may cause approximately 2\% (N = 0.65 million, 95\% CI 0.55-0.74) of African American adults with T2D to remain undiagnosed when screened with HbA1c. Limitations include the smaller sample sizes for non-European ancestries and the inability to classify approximately one-third of the variants. Further studies in large multiethnic cohorts with HbA1c, glycemic, and erythrocytic traits are required to better determine the biological action of the unclassified variants.

CONCLUSIONS: As G6PD deficiency can be clinically silent until illness strikes, we recommend investigation of the possible benefits of screening for the G6PD genotype along with using HbA1c to diagnose T2D in populations of African ancestry or groups where G6PD deficiency is common. Screening with direct glucose measurements, or genetically-informed HbA1c diagnostic thresholds in people with G6PD deficiency, may be required to avoid missed or delayed diagnoses.

}, keywords = {Diabetes Mellitus, Type 2, Genetic Variation, Genome-Wide Association Study, Glycated Hemoglobin A, Humans, Phenotype, Risk}, issn = {1549-1676}, doi = {10.1371/journal.pmed.1002383}, author = {Wheeler, Eleanor and Leong, Aaron and Liu, Ching-Ti and Hivert, Marie-France and Strawbridge, Rona J and Podmore, Clara and Li, Man and Yao, Jie and Sim, Xueling and Hong, Jaeyoung and Chu, Audrey Y and Zhang, Weihua and Wang, Xu and Chen, Peng and Maruthur, Nisa M and Porneala, Bianca C and Sharp, Stephen J and Jia, Yucheng and Kabagambe, Edmond K and Chang, Li-Ching and Chen, Wei-Min and Elks, Cathy E and Evans, Daniel S and Fan, Qiao and Giulianini, Franco and Go, Min Jin and Hottenga, Jouke-Jan and Hu, Yao and Jackson, Anne U and Kanoni, Stavroula and Kim, Young Jin and Kleber, Marcus E and Ladenvall, Claes and Lecoeur, C{\'e}cile and Lim, Sing-Hui and Lu, Yingchang and Mahajan, Anubha and Marzi, Carola and Nalls, Mike A and Navarro, Pau and Nolte, Ilja M and Rose, Lynda M and Rybin, Denis V and Sanna, Serena and Shi, Yuan and Stram, Daniel O and Takeuchi, Fumihiko and Tan, Shu Pei and van der Most, Peter J and van Vliet-Ostaptchouk, Jana V and Wong, Andrew and Yengo, Loic and Zhao, Wanting and Goel, Anuj and Martinez Larrad, Maria Teresa and Radke, D{\"o}rte and Salo, Perttu and Tanaka, Toshiko and van Iperen, Erik P A and Abecasis, Goncalo and Afaq, Saima and Alizadeh, Behrooz Z and Bertoni, Alain G and Bonnefond, Am{\'e}lie and B{\"o}ttcher, Yvonne and Bottinger, Erwin P and Campbell, Harry and Carlson, Olga D and Chen, Chien-Hsiun and Cho, Yoon Shin and Garvey, W Timothy and Gieger, Christian and Goodarzi, Mark O and Grallert, Harald and Hamsten, Anders and Hartman, Catharina A and Herder, Christian and Hsiung, Chao Agnes and Huang, Jie and Igase, Michiya and Isono, Masato and Katsuya, Tomohiro and Khor, Chiea-Chuen and Kiess, Wieland and Kohara, Katsuhiko and Kovacs, Peter and Lee, Juyoung and Lee, Wen-Jane and Lehne, Benjamin and Li, Huaixing and Liu, Jianjun and Lobbens, Stephane and Luan, Jian{\textquoteright}an and Lyssenko, Valeriya and Meitinger, Thomas and Miki, Tetsuro and Miljkovic, Iva and Moon, Sanghoon and Mulas, Antonella and M{\"u}ller, Gabriele and M{\"u}ller-Nurasyid, Martina and Nagaraja, Ramaiah and Nauck, Matthias and Pankow, James S and Polasek, Ozren and Prokopenko, Inga and Ramos, Paula S and Rasmussen-Torvik, Laura and Rathmann, Wolfgang and Rich, Stephen S and Robertson, Neil R and Roden, Michael and Roussel, Ronan and Rudan, Igor and Scott, Robert A and Scott, William R and Sennblad, Bengt and Siscovick, David S and Strauch, Konstantin and Sun, Liang and Swertz, Morris and Tajuddin, Salman M and Taylor, Kent D and Teo, Yik-Ying and Tham, Yih Chung and T{\"o}njes, Anke and Wareham, Nicholas J and Willemsen, Gonneke and Wilsgaard, Tom and Hingorani, Aroon D and Egan, Josephine and Ferrucci, Luigi and Hovingh, G Kees and Jula, Antti and Kivimaki, Mika and Kumari, Meena and Nj{\o}lstad, Inger and Palmer, Colin N A and Serrano R{\'\i}os, Manuel and Stumvoll, Michael and Watkins, Hugh and Aung, Tin and Bl{\"u}her, Matthias and Boehnke, Michael and Boomsma, Dorret I and Bornstein, Stefan R and Chambers, John C and Chasman, Daniel I and Chen, Yii-Der Ida and Chen, Yduan-Tsong and Cheng, Ching-Yu and Cucca, Francesco and de Geus, Eco J C and Deloukas, Panos and Evans, Michele K and Fornage, Myriam and Friedlander, Yechiel and Froguel, Philippe and Groop, Leif and Gross, Myron D and Harris, Tamara B and Hayward, Caroline and Heng, Chew-Kiat and Ingelsson, Erik and Kato, Norihiro and Kim, Bong-Jo and Koh, Woon-Puay and Kooner, Jaspal S and K{\"o}rner, Antje and Kuh, Diana and Kuusisto, Johanna and Laakso, Markku and Lin, Xu and Liu, Yongmei and Loos, Ruth J F and Magnusson, Patrik K E and M{\"a}rz, Winfried and McCarthy, Mark I and Oldehinkel, Albertine J and Ong, Ken K and Pedersen, Nancy L and Pereira, Mark A and Peters, Annette and Ridker, Paul M and Sabanayagam, Charumathi and Sale, Michele and Saleheen, Danish and Saltevo, Juha and Schwarz, Peter Eh and Sheu, Wayne H H and Snieder, Harold and Spector, Timothy D and Tabara, Yasuharu and Tuomilehto, Jaakko and van Dam, Rob M and Wilson, James G and Wilson, James F and Wolffenbuttel, Bruce H R and Wong, Tien Yin and Wu, Jer-Yuarn and Yuan, Jian-Min and Zonderman, Alan B and Soranzo, Nicole and Guo, Xiuqing and Roberts, David J and Florez, Jose C and Sladek, Robert and Dupuis, Jos{\'e}e and Morris, Andrew P and Tai, E-Shyong and Selvin, Elizabeth and Rotter, Jerome I and Langenberg, Claudia and Barroso, In{\^e}s and Meigs, James B} }