%0 Journal Article %J PLoS Genet %D 2011 %T Enhanced statistical tests for GWAS in admixed populations: assessment using African Americans from CARe and a Breast Cancer Consortium. %A Pasaniuc, Bogdan %A Zaitlen, Noah %A Lettre, Guillaume %A Chen, Gary K %A Tandon, Arti %A Kao, W H Linda %A Ruczinski, Ingo %A Fornage, Myriam %A Siscovick, David S %A Zhu, Xiaofeng %A Larkin, Emma %A Lange, Leslie A %A Cupples, L Adrienne %A Yang, Qiong %A Akylbekova, Ermeg L %A Musani, Solomon K %A Divers, Jasmin %A Mychaleckyj, Joe %A Li, Mingyao %A Papanicolaou, George J %A Millikan, Robert C %A Ambrosone, Christine B %A John, Esther M %A Bernstein, Leslie %A Zheng, Wei %A Hu, Jennifer J %A Ziegler, Regina G %A Nyante, Sarah J %A Bandera, Elisa V %A Ingles, Sue A %A Press, Michael F %A Chanock, Stephen J %A Deming, Sandra L %A Rodriguez-Gil, Jorge L %A Palmer, Cameron D %A Buxbaum, Sarah %A Ekunwe, Lynette %A Hirschhorn, Joel N %A Henderson, Brian E %A Myers, Simon %A Haiman, Christopher A %A Reich, David %A Patterson, Nick %A Wilson, James G %A Price, Alkes L %K African Americans %K Algorithms %K Breast Neoplasms %K Chromosome Mapping %K Coronary Disease %K Diabetes Mellitus, Type 2 %K Female %K Gene Frequency %K Genetic Variation %K Genetics, Population %K Genome, Human %K Genome-Wide Association Study %K Genotype %K Humans %K Linkage Disequilibrium %K Male %K Odds Ratio %K Phenotype %K Polymorphism, Single Nucleotide %K Principal Component Analysis %K Receptor, Fibroblast Growth Factor, Type 2 %K Software %X

While genome-wide association studies (GWAS) have primarily examined populations of European ancestry, more recent studies often involve additional populations, including admixed populations such as African Americans and Latinos. In admixed populations, linkage disequilibrium (LD) exists both at a fine scale in ancestral populations and at a coarse scale (admixture-LD) due to chromosomal segments of distinct ancestry. Disease association statistics in admixed populations have previously considered SNP association (LD mapping) or admixture association (mapping by admixture-LD), but not both. Here, we introduce a new statistical framework for combining SNP and admixture association in case-control studies, as well as methods for local ancestry-aware imputation. We illustrate the gain in statistical power achieved by these methods by analyzing data of 6,209 unrelated African Americans from the CARe project genotyped on the Affymetrix 6.0 chip, in conjunction with both simulated and real phenotypes, as well as by analyzing the FGFR2 locus using breast cancer GWAS data from 5,761 African-American women. We show that, at typed SNPs, our method yields an 8% increase in statistical power for finding disease risk loci compared to the power achieved by standard methods in case-control studies. At imputed SNPs, we observe an 11% increase in statistical power for mapping disease loci when our local ancestry-aware imputation framework and the new scoring statistic are jointly employed. Finally, we show that our method increases statistical power in regions harboring the causal SNP in the case when the causal SNP is untyped and cannot be imputed. Our methods and our publicly available software are broadly applicable to GWAS in admixed populations.

%B PLoS Genet %V 7 %P e1001371 %8 2011 Apr %G eng %N 4 %1 http://www.ncbi.nlm.nih.gov/pubmed/21541012?dopt=Abstract %R 10.1371/journal.pgen.1001371 %0 Journal Article %J Nat Genet %D 2013 %T A meta-analysis identifies new loci associated with body mass index in individuals of African ancestry. %A Monda, Keri L %A Chen, Gary K %A Taylor, Kira C %A Palmer, Cameron %A Edwards, Todd L %A Lange, Leslie A %A Ng, Maggie C Y %A Adeyemo, Adebowale A %A Allison, Matthew A %A Bielak, Lawrence F %A Chen, Guanjie %A Graff, Mariaelisa %A Irvin, Marguerite R %A Rhie, Suhn K %A Li, Guo %A Liu, Yongmei %A Liu, Youfang %A Lu, Yingchang %A Nalls, Michael A %A Sun, Yan V %A Wojczynski, Mary K %A Yanek, Lisa R %A Aldrich, Melinda C %A Ademola, Adeyinka %A Amos, Christopher I %A Bandera, Elisa V %A Bock, Cathryn H %A Britton, Angela %A Broeckel, Ulrich %A Cai, Quiyin %A Caporaso, Neil E %A Carlson, Chris S %A Carpten, John %A Casey, Graham %A Chen, Wei-Min %A Chen, Fang %A Chen, Yii-der I %A Chiang, Charleston W K %A Coetzee, Gerhard A %A Demerath, Ellen %A Deming-Halverson, Sandra L %A Driver, Ryan W %A Dubbert, Patricia %A Feitosa, Mary F %A Feng, Ye %A Freedman, Barry I %A Gillanders, Elizabeth M %A Gottesman, Omri %A Guo, Xiuqing %A Haritunians, Talin %A Harris, Tamara %A Harris, Curtis C %A Hennis, Anselm J M %A Hernandez, Dena G %A McNeill, Lorna H %A Howard, Timothy D %A Howard, Barbara V %A Howard, Virginia J %A Johnson, Karen C %A Kang, Sun J %A Keating, Brendan J %A Kolb, Suzanne %A Kuller, Lewis H %A Kutlar, Abdullah %A Langefeld, Carl D %A Lettre, Guillaume %A Lohman, Kurt %A Lotay, Vaneet %A Lyon, Helen %A Manson, JoAnn E %A Maixner, William %A Meng, Yan A %A Monroe, Kristine R %A Morhason-Bello, Imran %A Murphy, Adam B %A Mychaleckyj, Josyf C %A Nadukuru, Rajiv %A Nathanson, Katherine L %A Nayak, Uma %A N'diaye, Amidou %A Nemesure, Barbara %A Wu, Suh-Yuh %A Leske, M Cristina %A Neslund-Dudas, Christine %A Neuhouser, Marian %A Nyante, Sarah %A Ochs-Balcom, Heather %A Ogunniyi, Adesola %A Ogundiran, Temidayo O %A Ojengbede, Oladosu %A Olopade, Olufunmilayo I %A Palmer, Julie R %A Ruiz-Narvaez, Edward A %A Palmer, Nicholette D %A Press, Michael F %A Rampersaud, Evandine %A Rasmussen-Torvik, Laura J %A Rodriguez-Gil, Jorge L %A Salako, Babatunde %A Schadt, Eric E %A Schwartz, Ann G %A Shriner, Daniel A %A Siscovick, David %A Smith, Shad B %A Wassertheil-Smoller, Sylvia %A Speliotes, Elizabeth K %A Spitz, Margaret R %A Sucheston, Lara %A Taylor, Herman %A Tayo, Bamidele O %A Tucker, Margaret A %A Van Den Berg, David J %A Edwards, Digna R Velez %A Wang, Zhaoming %A Wiencke, John K %A Winkler, Thomas W %A Witte, John S %A Wrensch, Margaret %A Wu, Xifeng %A Yang, James J %A Levin, Albert M %A Young, Taylor R %A Zakai, Neil A %A Cushman, Mary %A Zanetti, Krista A %A Zhao, Jing Hua %A Zhao, Wei %A Zheng, Yonglan %A Zhou, Jie %A Ziegler, Regina G %A Zmuda, Joseph M %A Fernandes, Jyotika K %A Gilkeson, Gary S %A Kamen, Diane L %A Hunt, Kelly J %A Spruill, Ida J %A Ambrosone, Christine B %A Ambs, Stefan %A Arnett, Donna K %A Atwood, Larry %A Becker, Diane M %A Berndt, Sonja I %A Bernstein, Leslie %A Blot, William J %A Borecki, Ingrid B %A Bottinger, Erwin P %A Bowden, Donald W %A Burke, Gregory %A Chanock, Stephen J %A Cooper, Richard S %A Ding, Jingzhong %A Duggan, David %A Evans, Michele K %A Fox, Caroline %A Garvey, W Timothy %A Bradfield, Jonathan P %A Hakonarson, Hakon %A Grant, Struan F A %A Hsing, Ann %A Chu, Lisa %A Hu, Jennifer J %A Huo, Dezheng %A Ingles, Sue A %A John, Esther M %A Jordan, Joanne M %A Kabagambe, Edmond K %A Kardia, Sharon L R %A Kittles, Rick A %A Goodman, Phyllis J %A Klein, Eric A %A Kolonel, Laurence N %A Le Marchand, Loïc %A Liu, Simin %A McKnight, Barbara %A Millikan, Robert C %A Mosley, Thomas H %A Padhukasahasram, Badri %A Williams, L Keoki %A Patel, Sanjay R %A Peters, Ulrike %A Pettaway, Curtis A %A Peyser, Patricia A %A Psaty, Bruce M %A Redline, Susan %A Rotimi, Charles N %A Rybicki, Benjamin A %A Sale, Michèle M %A Schreiner, Pamela J %A Signorello, Lisa B %A Singleton, Andrew B %A Stanford, Janet L %A Strom, Sara S %A Thun, Michael J %A Vitolins, Mara %A Zheng, Wei %A Moore, Jason H %A Williams, Scott M %A Ketkar, Shamika %A Zhu, Xiaofeng %A Zonderman, Alan B %A Kooperberg, Charles %A Papanicolaou, George J %A Henderson, Brian E %A Reiner, Alex P %A Hirschhorn, Joel N %A Loos, Ruth J F %A North, Kari E %A Haiman, Christopher A %K African Americans %K Body Mass Index %K Case-Control Studies %K Gene Frequency %K Genetic Loci %K Genetic Predisposition to Disease %K Genome-Wide Association Study %K Humans %K Linkage Disequilibrium %K Obesity %K Polymorphism, Single Nucleotide %X

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 × 10(-11)) and another at 7p15 when we included data from the GIANT consortium (MIR148A-NFE2L3, rs10261878, P = 1.2 × 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 × 10(-8)). Thirty-two of the 36 previously established BMI variants showed directionally consistent effect estimates in our GWAS (binomial P = 9.7 × 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.

%B Nat Genet %V 45 %P 690-6 %8 2013 Jun %G eng %N 6 %1 http://www.ncbi.nlm.nih.gov/pubmed/23583978?dopt=Abstract %R 10.1038/ng.2608 %0 Journal Article %J Hum Mol Genet %D 2014 %T Meta-analysis of loci associated with age at natural menopause in African-American women. %A Chen, Christina T L %A Liu, Ching-Ti %A Chen, Gary K %A Andrews, Jeanette S %A Arnold, Alice M %A Dreyfus, Jill %A Franceschini, Nora %A Garcia, Melissa E %A Kerr, Kathleen F %A Li, Guo %A Lohman, Kurt K %A Musani, Solomon K %A Nalls, Michael A %A Raffel, Leslie J %A Smith, Jennifer %A Ambrosone, Christine B %A Bandera, Elisa V %A Bernstein, Leslie %A Britton, Angela %A Brzyski, Robert G %A Cappola, Anne %A Carlson, Christopher S %A Couper, David %A Deming, Sandra L %A Goodarzi, Mark O %A Heiss, Gerardo %A John, Esther M %A Lu, Xiaoning %A Le Marchand, Loïc %A Marciante, Kristin %A McKnight, Barbara %A Millikan, Robert %A Nock, Nora L %A Olshan, Andrew F %A Press, Michael F %A Vaiyda, Dhananjay %A Woods, Nancy F %A Taylor, Herman A %A Zhao, Wei %A Zheng, Wei %A Evans, Michele K %A Harris, Tamara B %A Henderson, Brian E %A Kardia, Sharon L R %A Kooperberg, Charles %A Liu, Yongmei %A Mosley, Thomas H %A Psaty, Bruce %A Wellons, Melissa %A Windham, Beverly G %A Zonderman, Alan B %A Cupples, L Adrienne %A Demerath, Ellen W %A Haiman, Christopher %A Murabito, Joanne M %A Rajkovic, Aleksandar %K African Americans %K Age Factors %K Chromosomes, Human %K European Continental Ancestry Group %K Female %K Genetic Loci %K Genetic Variation %K Genome-Wide Association Study %K Humans %K Menopause %K United States %X

Age at menopause marks the end of a woman's reproductive life and its timing associates with risks for cancer, cardiovascular and bone disorders. GWAS and candidate gene studies conducted in women of European ancestry have identified 27 loci associated with age at menopause. The relevance of these loci to women of African ancestry has not been previously studied. We therefore sought to uncover additional menopause loci and investigate the relevance of European menopause loci by performing a GWAS meta-analysis in 6510 women with African ancestry derived from 11 studies across the USA. We did not identify any additional loci significantly associated with age at menopause in African Americans. We replicated the associations between six loci and age at menopause (P-value < 0.05): AMHR2, RHBLD2, PRIM1, HK3/UMC1, BRSK1/TMEM150B and MCM8. In addition, associations of 14 loci are directionally consistent with previous reports. We provide evidence that genetic variants influencing reproductive traits identified in European populations are also important in women of African ancestry residing in USA.

%B Hum Mol Genet %V 23 %P 3327-42 %8 2014 Jun 15 %G eng %N 12 %1 http://www.ncbi.nlm.nih.gov/pubmed/24493794?dopt=Abstract %R 10.1093/hmg/ddu041