@article {6633, title = {Consistent directions of effect for established type 2 diabetes risk variants across populations: the population architecture using Genomics and Epidemiology (PAGE) Consortium.}, journal = {Diabetes}, volume = {61}, year = {2012}, month = {2012 Jun}, pages = {1642-7}, abstract = {

Common genetic risk variants for type 2 diabetes (T2D) have primarily been identified in populations of European and Asian ancestry. We tested whether the direction of association with 20 T2D risk variants generalizes across six major racial/ethnic groups in the U.S. as part of the Population Architecture using Genomics and Epidemiology Consortium (16,235 diabetes case and 46,122 control subjects of European American, African American, Hispanic, East Asian, American Indian, and Native Hawaiian ancestry). The percentage of positive (odds ratio [OR] >1 for putative risk allele) associations ranged from 69\% in American Indians to 100\% in European Americans. Of the nine variants where we observed significant heterogeneity of effect by racial/ethnic group (P(heterogeneity) < 0.05), eight were positively associated with risk (OR >1) in at least five groups. The marked directional consistency of association observed for most genetic variants across populations implies a shared functional common variant in each region. Fine-mapping of all loci will be required to reveal markers of risk that are important within and across populations.

}, keywords = {Adult, Aged, Aged, 80 and over, Alleles, Diabetes Mellitus, Type 2, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, Genotype, Humans, Male, Metagenomics, Middle Aged, Population Groups, Risk, Risk Factors}, issn = {1939-327X}, doi = {10.2337/db11-1296}, author = {Haiman, Christopher A and Fesinmeyer, Megan D and Spencer, Kylee L and B{\r u}zkov{\'a}, Petra and Voruganti, V Saroja and Wan, Peggy and Haessler, Jeff and Franceschini, Nora and Monroe, Kristine R and Howard, Barbara V and Jackson, Rebecca D and Florez, Jose C and Kolonel, Laurence N and Buyske, Steven and Goodloe, Robert J and Liu, Simin and Manson, JoAnn E and Meigs, James B and Waters, Kevin and Mukamal, Kenneth J and Pendergrass, Sarah A and Shrader, Peter and Wilkens, Lynne R and Hindorff, Lucia A and Ambite, Jose Luis and North, Kari E and Peters, Ulrike and Crawford, Dana C and Le Marchand, Lo{\"\i}c and Pankow, James S} } @article {6083, title = {Fine-mapping and initial characterization of QT interval loci in African Americans.}, journal = {PLoS Genet}, volume = {8}, year = {2012}, month = {2012}, pages = {e1002870}, abstract = {

The QT interval (QT) is heritable and its prolongation is a risk factor for ventricular tachyarrhythmias and sudden death. Most genetic studies of QT have examined European ancestral populations; however, the increased genetic diversity in African Americans provides opportunities to narrow association signals and identify population-specific variants. We therefore evaluated 6,670 SNPs spanning eleven previously identified QT loci in 8,644 African American participants from two Population Architecture using Genomics and Epidemiology (PAGE) studies: the Atherosclerosis Risk in Communities study and Women{\textquoteright}s Health Initiative Clinical Trial. Of the fifteen known independent QT variants at the eleven previously identified loci, six were significantly associated with QT in African American populations (P<=1.20{\texttimes}10(-4)): ATP1B1, PLN1, KCNQ1, NDRG4, and two NOS1AP independent signals. We also identified three population-specific signals significantly associated with QT in African Americans (P<=1.37{\texttimes}10(-5)): one at NOS1AP and two at ATP1B1. Linkage disequilibrium (LD) patterns in African Americans assisted in narrowing the region likely to contain the functional variants for several loci. For example, African American LD patterns showed that 0 SNPs were in LD with NOS1AP signal rs12143842, compared with European LD patterns that indicated 87 SNPs, which spanned 114.2 Kb, were in LD with rs12143842. Finally, bioinformatic-based characterization of the nine African American signals pointed to functional candidates located exclusively within non-coding regions, including predicted binding sites for transcription factors such as TBX5, which has been implicated in cardiac structure and conductance. In this detailed evaluation of QT loci, we identified several African Americans SNPs that better define the association with QT and successfully narrowed intervals surrounding established loci. These results demonstrate that the same loci influence variation in QT across multiple populations, that novel signals exist in African Americans, and that the SNPs identified as strong candidates for functional evaluation implicate gene regulatory dysfunction in QT prolongation.

}, keywords = {African Americans, Aged, Computational Biology, Electrocardiography, European Continental Ancestry Group, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Linkage Disequilibrium, Male, Metagenomics, Middle Aged, Polymorphism, Single Nucleotide, Quantitative Trait Loci, Quantitative Trait, Heritable, Risk Factors, Tachycardia, United States}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1002870}, author = {Avery, Christy L and Sethupathy, Praveen and Buyske, Steven and He, Qianchuan and Lin, Dan-Yu and Arking, Dan E and Carty, Cara L and Duggan, David and Fesinmeyer, Megan D and Hindorff, Lucia A and Jeff, Janina M and Klein, Liviu and Patton, Kristen K and Peters, Ulrike and Shohet, Ralph V and Sotoodehnia, Nona and Young, Alicia M and Kooperberg, Charles and Haiman, Christopher A and Mohlke, Karen L and Whitsel, Eric A and North, Kari E} } @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 {6626, title = {Fine Mapping and Identification of BMI Loci in African Americans.}, journal = {Am J Hum Genet}, volume = {93}, year = {2013}, month = {2013 Oct 3}, pages = {661-71}, abstract = {

Genome-wide association studies (GWASs) primarily performed in European-ancestry (EA) populations have identified numerous loci associated with body mass index (BMI). However, it is still unclear whether these GWAS loci can be generalized to other ethnic groups, such as African Americans (AAs). Furthermore, the putative functional variant or variants in these loci mostly remain under investigation. The overall lower linkage disequilibrium in AA compared to EA populations provides the opportunity to narrow in or fine-map these BMI-related loci. Therefore, we used the Metabochip to densely genotype and evaluate 21 BMI GWAS loci identified in EA studies in 29,151 AAs from the Population Architecture using Genomics and Epidemiology (PAGE) study. Eight of the 21 loci (SEC16B, TMEM18, ETV5, GNPDA2, TFAP2B, BDNF, FTO, and MC4R) were found to be associated with BMI in AAs at 5.8~{\texttimes} 10(-5). Within seven out of these eight loci, we found that, on average, a substantially smaller number of variants was correlated (r(2) > 0.5) with the most significant SNP in AA than in EA populations (16 versus 55). Conditional analyses revealed GNPDA2 harboring a potential additional independent signal. Moreover, Metabochip-wide discovery analyses revealed two BMI-related loci, BRE (rs116612809, p = 3.6~{\texttimes} 10(-8)) and DHX34 (rs4802349, p = 1.2~{\texttimes} 10(-7)), which were significant when adjustment was made for the total number of SNPs tested across the chip. These results demonstrate that fine mapping in AAs is a powerful approach for both narrowing in on the underlying causal variants in known loci and discovering BMI-related loci.

}, keywords = {Adult, African Americans, Aged, Aged, 80 and over, Body Mass Index, Female, Genetic Loci, Genetic Predisposition to Disease, Genome, Human, Genome-Wide Association Study, Genotype, Humans, Linkage Disequilibrium, Male, Middle Aged, Obesity, Polymorphism, Single Nucleotide, Young Adult}, issn = {1537-6605}, doi = {10.1016/j.ajhg.2013.08.012}, author = {Gong, Jian and Schumacher, Fredrick and Lim, Unhee and Hindorff, Lucia A and Haessler, Jeff and Buyske, Steven and Carlson, Christopher S and Rosse, Stephanie and B{\r u}zkov{\'a}, Petra and Fornage, Myriam and Gross, Myron and Pankratz, Nathan and Pankow, James S and Schreiner, Pamela J and Cooper, Richard and Ehret, Georg and Gu, C Charles and Houston, Denise and Irvin, Marguerite R and Jackson, Rebecca and Kuller, Lew and Henderson, Brian and Cheng, Iona and Wilkens, Lynne and Leppert, Mark and Lewis, Cora E and Li, Rongling and Nguyen, Khanh-Dung H and Goodloe, Robert and Farber-Eger, Eric and Boston, Jonathan and Dilks, Holli H and Ritchie, Marylyn D and Fowke, Jay and Pooler, Loreall and Graff, Misa and Fernandez-Rhodes, Lindsay and Cochrane, Barbara and Boerwinkle, Eric and Kooperberg, Charles and Matise, Tara C and Le Marchand, Lo{\"\i}c and Crawford, Dana C and Haiman, Christopher A and North, Kari E and Peters, Ulrike} } @article {6289, title = {Generalization and dilution of association results from European GWAS in populations of non-European ancestry: the PAGE study.}, journal = {PLoS Biol}, volume = {11}, year = {2013}, month = {2013 Sep}, pages = {e1001661}, abstract = {

The vast majority of genome-wide association study (GWAS) findings reported to date are from populations with European Ancestry (EA), and it is not yet clear how broadly the genetic associations described will generalize to populations of diverse ancestry. The Population Architecture Using Genomics and Epidemiology (PAGE) study is a consortium of multi-ancestry, population-based studies formed with the objective of refining our understanding of the genetic architecture of common traits emerging from GWAS. In the present analysis of five common diseases and traits, including body mass index, type 2 diabetes, and lipid levels, we compare direction and magnitude of effects for GWAS-identified variants in multiple non-EA populations against EA findings. We demonstrate that, in all populations analyzed, a significant majority of GWAS-identified variants have allelic associations in the same direction as in EA, with none showing a statistically significant effect in the opposite direction, after adjustment for multiple testing. However, 25\% of tagSNPs identified in EA GWAS have significantly different effect sizes in at least one non-EA population, and these differential effects were most frequent in African Americans where all differential effects were diluted toward the null. We demonstrate that differential LD between tagSNPs and functional variants within populations contributes significantly to dilute effect sizes in this population. Although most variants identified from GWAS in EA populations generalize to all non-EA populations assessed, genetic models derived from GWAS findings in EA may generate spurious results in non-EA populations due to differential effect sizes. Regardless of the origin of the differential effects, caution should be exercised in applying any genetic risk prediction model based on tagSNPs outside of the ancestry group in which it was derived. Models based directly on functional variation may generalize more robustly, but the identification of functional variants remains challenging.

}, keywords = {African Americans, Asian Americans, Body Mass Index, Diabetes Mellitus, Type 2, European Continental Ancestry Group, Gene Frequency, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, Hispanic Americans, Humans, Indians, North American, Lipids, Metagenomics, Oceanic Ancestry Group, Polymorphism, Single Nucleotide}, issn = {1545-7885}, doi = {10.1371/journal.pbio.1001661}, author = {Carlson, Christopher S and Matise, Tara C and North, Kari E and Haiman, Christopher A and Fesinmeyer, Megan D and Buyske, Steven and Schumacher, Fredrick R and Peters, Ulrike and Franceschini, Nora and Ritchie, Marylyn D and Duggan, David J and Spencer, Kylee L and Dumitrescu, Logan and Eaton, Charles B and Thomas, Fridtjof and Young, Alicia and Carty, Cara and Heiss, Gerardo and Le Marchand, Lo{\"\i}c and Crawford, Dana C and Hindorff, Lucia A and Kooperberg, Charles L} } @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 {6078, title = {A meta-analysis identifies new loci associated with body mass index in individuals of African ancestry.}, journal = {Nat Genet}, volume = {45}, year = {2013}, month = {2013 Jun}, pages = {690-6}, abstract = {

Genome-wide association studies (GWAS) have identified 36 loci associated with body mass index (BMI), predominantly in populations of European ancestry. We conducted a meta-analysis to examine the association of >3.2 million SNPs with BMI in 39,144 men and women of African ancestry and followed up the most significant associations in an additional 32,268 individuals of African ancestry. We identified one new locus at 5q33 (GALNT10, rs7708584, P = 3.4 {\texttimes} 10(-11)) and another at 7p15 when we included data from the GIANT consortium (MIR148A-NFE2L3, rs10261878, P = 1.2 {\texttimes} 10(-10)). We also found suggestive evidence of an association at a third locus at 6q16 in the African-ancestry sample (KLHL32, rs974417, P = 6.9 {\texttimes} 10(-8)). Thirty-two of the 36 previously established BMI variants showed directionally consistent effect estimates in our GWAS (binomial P = 9.7 {\texttimes} 10(-7)), five of which reached genome-wide significance. These findings provide strong support for shared BMI loci across populations, as well as for the utility of studying ancestrally diverse populations.

}, keywords = {African Americans, Body Mass Index, Case-Control Studies, Gene Frequency, Genetic Loci, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Linkage Disequilibrium, Obesity, Polymorphism, Single Nucleotide}, issn = {1546-1718}, doi = {10.1038/ng.2608}, author = {Monda, Keri L and Chen, Gary K and Taylor, Kira C and Palmer, Cameron and Edwards, Todd L and Lange, Leslie A and Ng, Maggie C Y and Adeyemo, Adebowale A and Allison, Matthew A and Bielak, Lawrence F and Chen, Guanjie and Graff, Mariaelisa and Irvin, Marguerite R and Rhie, Suhn K and Li, Guo and Liu, Yongmei and Liu, Youfang and Lu, Yingchang and Nalls, Michael A and Sun, Yan V and Wojczynski, Mary K and Yanek, Lisa R and Aldrich, Melinda C and Ademola, Adeyinka and Amos, Christopher I and Bandera, Elisa V and Bock, Cathryn H and Britton, Angela and Broeckel, Ulrich and Cai, Quiyin and Caporaso, Neil E and Carlson, Chris S and Carpten, John and Casey, Graham and Chen, Wei-Min and Chen, Fang and Chen, Yii-der I and Chiang, Charleston W K and Coetzee, Gerhard A and Demerath, Ellen and Deming-Halverson, Sandra L and Driver, Ryan W and Dubbert, Patricia and Feitosa, Mary F and Feng, Ye and Freedman, Barry I and Gillanders, Elizabeth M and Gottesman, Omri and Guo, Xiuqing and Haritunians, Talin and Harris, Tamara and Harris, Curtis C and Hennis, Anselm J M and Hernandez, Dena G and McNeill, Lorna H and Howard, Timothy D and Howard, Barbara V and Howard, Virginia J and Johnson, Karen C and Kang, Sun J and Keating, Brendan J and Kolb, Suzanne and Kuller, Lewis H and Kutlar, Abdullah and Langefeld, Carl D and Lettre, Guillaume and Lohman, Kurt and Lotay, Vaneet and Lyon, Helen and Manson, JoAnn E and Maixner, William and Meng, Yan A and Monroe, Kristine R and Morhason-Bello, Imran and Murphy, Adam B and Mychaleckyj, Josyf C and Nadukuru, Rajiv and Nathanson, Katherine L and Nayak, Uma and N{\textquoteright}diaye, Amidou and Nemesure, Barbara and Wu, Suh-Yuh and Leske, M Cristina and Neslund-Dudas, Christine and Neuhouser, Marian and Nyante, Sarah and Ochs-Balcom, Heather and Ogunniyi, Adesola and Ogundiran, Temidayo O and Ojengbede, Oladosu and Olopade, Olufunmilayo I and Palmer, Julie R and Ruiz-Narvaez, Edward A and Palmer, Nicholette D and Press, Michael F and Rampersaud, Evandine and Rasmussen-Torvik, Laura J and Rodriguez-Gil, Jorge L and Salako, Babatunde and Schadt, Eric E and Schwartz, Ann G and Shriner, Daniel A and Siscovick, David and Smith, Shad B and Wassertheil-Smoller, Sylvia and Speliotes, Elizabeth K and Spitz, Margaret R and Sucheston, Lara and Taylor, Herman and Tayo, Bamidele O and Tucker, Margaret A and Van Den Berg, David J and Edwards, Digna R Velez and Wang, Zhaoming and Wiencke, John K and Winkler, Thomas W and Witte, John S and Wrensch, Margaret and Wu, Xifeng and Yang, James J and Levin, Albert M and Young, Taylor R and Zakai, Neil A and Cushman, Mary and Zanetti, Krista A and Zhao, Jing Hua and Zhao, Wei and Zheng, Yonglan and Zhou, Jie and Ziegler, Regina G and Zmuda, Joseph M and Fernandes, Jyotika K and Gilkeson, Gary S and Kamen, Diane L and Hunt, Kelly J and Spruill, Ida J and Ambrosone, Christine B and Ambs, Stefan and Arnett, Donna K and Atwood, Larry and Becker, Diane M and Berndt, Sonja I and Bernstein, Leslie and Blot, William J and Borecki, Ingrid B and Bottinger, Erwin P and Bowden, Donald W and Burke, Gregory and Chanock, Stephen J and Cooper, Richard S and Ding, Jingzhong and Duggan, David and Evans, Michele K and Fox, Caroline and Garvey, W Timothy and Bradfield, Jonathan P and Hakonarson, Hakon and Grant, Struan F A and Hsing, Ann and Chu, Lisa and Hu, Jennifer J and Huo, Dezheng and Ingles, Sue A and John, Esther M and Jordan, Joanne M and Kabagambe, Edmond K and Kardia, Sharon L R and Kittles, Rick A and Goodman, Phyllis J and Klein, Eric A and Kolonel, Laurence N and Le Marchand, Lo{\"\i}c and Liu, Simin and McKnight, Barbara and Millikan, Robert C and Mosley, Thomas H and Padhukasahasram, Badri and Williams, L Keoki and Patel, Sanjay R and Peters, Ulrike and Pettaway, Curtis A and Peyser, Patricia A and Psaty, Bruce M and Redline, Susan and Rotimi, Charles N and Rybicki, Benjamin A and Sale, Mich{\`e}le M and Schreiner, Pamela J and Signorello, Lisa B and Singleton, Andrew B and Stanford, Janet L and Strom, Sara S and Thun, Michael J and Vitolins, Mara and Zheng, Wei and Moore, Jason H and Williams, Scott M and Ketkar, Shamika and Zhu, Xiaofeng and Zonderman, Alan B and Kooperberg, Charles and Papanicolaou, George J and Henderson, Brian E and Reiner, Alex P and Hirschhorn, Joel N and Loos, Ruth J F and North, Kari E and Haiman, Christopher A} } @article {6628, title = {A systematic mapping approach of 16q12.2/FTO and BMI in more than 20,000 African Americans narrows in on the underlying functional variation: results from the Population Architecture using Genomics and Epidemiology (PAGE) study.}, journal = {PLoS Genet}, volume = {9}, year = {2013}, month = {2013}, pages = {e1003171}, abstract = {

Genetic variants in intron 1 of the fat mass- and obesity-associated (FTO) gene have been consistently associated with body mass index (BMI) in Europeans. However, follow-up studies in African Americans (AA) have shown no support for some of the most consistently BMI-associated FTO index single nucleotide polymorphisms (SNPs). This is most likely explained by different race-specific linkage disequilibrium (LD) patterns and lower correlation overall in AA, which provides the opportunity to fine-map this region and narrow in on the functional variant. To comprehensively explore the 16q12.2/FTO locus and to search for second independent signals in the broader region, we fine-mapped a 646-kb region, encompassing the large FTO gene and the flanking gene RPGRIP1L by investigating a total of 3,756 variants (1,529 genotyped and 2,227 imputed variants) in 20,488 AAs across five studies. We observed associations between BMI and variants in the known FTO intron 1 locus: the SNP with the most significant p-value, rs56137030 (8.3 {\texttimes} 10(-6)) had not been highlighted in previous studies. While rs56137030was correlated at r(2)>0.5 with 103 SNPs in Europeans (including the GWAS index SNPs), this number was reduced to 28 SNPs in AA. Among rs56137030 and the 28 correlated SNPs, six were located within candidate intronic regulatory elements, including rs1421085, for which we predicted allele-specific binding affinity for the transcription factor CUX1, which has recently been implicated in the regulation of FTO. We did not find strong evidence for a second independent signal in the broader region. In summary, this large fine-mapping study in AA has substantially reduced the number of common alleles that are likely to be functional candidates of the known FTO locus. Importantly our study demonstrated that comprehensive fine-mapping in AA provides a powerful approach to narrow in on the functional candidate(s) underlying the initial GWAS findings in European populations.

}, keywords = {Adaptor Proteins, Signal Transducing, Adult, African Americans, Aged, Aged, 80 and over, Alleles, Body Mass Index, Chromosome Mapping, Continental Population Groups, European Continental Ancestry Group, Female, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Linkage Disequilibrium, Male, Metagenomics, Middle Aged, Obesity, Proteins}, issn = {1553-7404}, doi = {10.1371/journal.pgen.1003171}, author = {Peters, Ulrike and North, Kari E and Sethupathy, Praveen and Buyske, Steve and Haessler, Jeff and Jiao, Shuo and Fesinmeyer, Megan D and Jackson, Rebecca D and Kuller, Lew H and Rajkovic, Aleksandar and Lim, Unhee and Cheng, Iona and Schumacher, Fred and Wilkens, Lynne and Li, Rongling and Monda, Keri and Ehret, Georg and Nguyen, Khanh-Dung H and Cooper, Richard and Lewis, Cora E and Leppert, Mark and Irvin, Marguerite R and Gu, C Charles and Houston, Denise and B{\r u}zkov{\'a}, Petra and Ritchie, Marylyn and Matise, Tara C and Le Marchand, Lo{\"\i}c and Hindorff, Lucia A and Crawford, Dana C and Haiman, Christopher A and Kooperberg, Charles} } @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 {6849, title = {Rare and Coding Region Genetic Variants Associated With Risk of Ischemic Stroke: The NHLBI Exome Sequence Project.}, journal = {JAMA Neurol}, volume = {72}, year = {2015}, month = {2015 Jul}, pages = {781-8}, abstract = {

IMPORTANCE: Stroke is the second leading cause of death and the third leading cause of years of life lost. Genetic factors contribute to stroke prevalence, and candidate gene and genome-wide association studies (GWAS) have identified variants associated with ischemic stroke risk. These variants often have small effects without obvious biological significance. Exome sequencing may discover predicted protein-altering variants with a potentially large effect on ischemic stroke risk.

OBJECTIVE: To investigate the contribution of rare and common genetic variants to ischemic stroke risk by targeting the protein-coding regions of the human genome.

DESIGN, SETTING, AND PARTICIPANTS: The National Heart, Lung, and Blood Institute (NHLBI) Exome Sequencing Project (ESP) analyzed approximately 6000 participants from numerous cohorts of European and African ancestry. For discovery, 365 cases of ischemic stroke (small-vessel and large-vessel subtypes) and 809 European ancestry controls were sequenced; for replication, 47 affected sibpairs concordant for stroke subtype and an African American case-control series were sequenced, with 1672 cases and 4509 European ancestry controls genotyped. The ESP{\textquoteright}s exome sequencing and genotyping started on January 1, 2010, and continued through June 30, 2012. Analyses were conducted on the full data set between July 12, 2012, and July 13, 2013.

MAIN OUTCOMES AND MEASURES: Discovery of new variants or genes contributing to ischemic stroke risk and subtype (primary analysis) and determination of support for protein-coding variants contributing to risk in previously published candidate genes (secondary analysis).

RESULTS: We identified 2 novel genes associated with an increased risk of ischemic stroke: a protein-coding variant in PDE4DIP (rs1778155; odds ratio, 2.15; P = 2.63 {\texttimes} 10(-8)) with an intracellular signal transduction mechanism and in ACOT4 (rs35724886; odds ratio, 2.04; P = 1.24 {\texttimes} 10(-7)) with a fatty acid metabolism; confirmation of PDE4DIP was observed in affected sibpair families with large-vessel stroke subtype and in African Americans. Replication of protein-coding variants in candidate genes was observed for 2 previously reported GWAS associations: ZFHX3 (cardioembolic stroke) and ABCA1 (large-vessel stroke).

CONCLUSIONS AND RELEVANCE: Exome sequencing discovered 2 novel genes and mechanisms, PDE4DIP and ACOT4, associated with increased risk for ischemic stroke. In addition, ZFHX3 and ABCA1 were discovered to have protein-coding variants associated with ischemic stroke. These results suggest that genetic variation in novel pathways contributes to ischemic stroke risk and serves as a target for prediction, prevention, and therapy.

}, keywords = {Aged, Brain Ischemia, Exome, Female, Genetic Predisposition to Disease, Genetic Variation, Genome-Wide Association Study, Humans, Male, Middle Aged, Muscle Proteins, National Heart, Lung, and Blood Institute (U.S.), Nuclear Proteins, Open Reading Frames, Palmitoyl-CoA Hydrolase, Stroke, United States}, issn = {2168-6157}, doi = {10.1001/jamaneurol.2015.0582}, author = {Auer, Paul L and Nalls, Mike and Meschia, James F and Worrall, Bradford B and Longstreth, W T and Seshadri, Sudha and Kooperberg, Charles and Burger, Kathleen M and Carlson, Christopher S and Carty, Cara L and Chen, Wei-Min and Cupples, L Adrienne and DeStefano, Anita L and Fornage, Myriam and Hardy, John and Hsu, Li and Jackson, Rebecca D and Jarvik, Gail P and Kim, Daniel S and Lakshminarayan, Kamakshi and Lange, Leslie A and Manichaikul, Ani and Quinlan, Aaron R and Singleton, Andrew B and Thornton, Timothy A and Nickerson, Deborah A and Peters, Ulrike and Rich, Stephen S} }