@article {1347, title = {Association of genetic variants and incident coronary heart disease in multiethnic cohorts: the PAGE study.}, journal = {Circ Cardiovasc Genet}, volume = {4}, year = {2011}, month = {2011 Dec}, pages = {661-72}, abstract = {

BACKGROUND: Genome-wide association studies identified several single nucleotide polymorphisms (SNP) associated with prevalent coronary heart disease (CHD), but less is known of associations with incident CHD. The association of 13 published CHD SNPs was examined in 5 ancestry groups of 4 large US prospective cohorts.

METHODS AND RESULTS: The analyses included incident coronary events over an average 9.1 to 15.7 follow-up person-years in up to 26 617 white individuals (6626 events), 8018 black individuals (914 events), 1903 Hispanic individuals (113 events), 3669 American Indian individuals (595 events), and 885 Asian/Pacific Islander individuals (66 events). We used Cox proportional hazards models (with additive mode of inheritance) adjusted for age, sex, and ancestry (as needed). Nine loci were statistically associated with incident CHD events in white participants: 9p21 (rs10757278; P=4.7 {\texttimes} 10(-41)), 16q23.1 (rs2549513; P=0.0004), 6p24.1 (rs499818; P=0.0002), 2q36.3 (rs2943634; P=6.7 {\texttimes} 10(-6)), MTHFD1L (rs6922269, P=5.1 {\texttimes} 10(-10)), APOE (rs429358; P=2.7{\texttimes}10(-18)), ZNF627 (rs4804611; P=5.0 {\texttimes} 10(-8)), CXCL12 (rs501120; P=1.4 {\texttimes} 10(-6)) and LPL (rs268; P=2.7 {\texttimes} 10(-17)). The 9p21 region showed significant between-study heterogeneity, with larger effects in individuals age 55 years or younger and in women. Inclusion of coronary revascularization procedures among the incident CHD events introduced heterogeneity. The SNPs were not associated with CHD in black participants, and associations varied in other US minorities.

CONCLUSIONS: Prospective analyses of white participants replicated several reported cross-sectional CHD-SNP associations.

}, keywords = {Aged, Aged, 80 and over, Continental Population Groups, Coronary Disease, Female, Genome-Wide Association Study, Humans, Male, Middle Aged, Polymorphism, Single Nucleotide, Prospective Studies}, issn = {1942-3268}, doi = {10.1161/CIRCGENETICS.111.960096}, author = {Franceschini, Nora and Carty, Cara and B{\r u}zkov{\'a}, Petra and Reiner, Alex P and Garrett, Tiana and Lin, Yi and V{\"o}ckler, Jens-S and Hindorff, Lucia A and Cole, Shelley A and Boerwinkle, Eric and Lin, Dan-Yu and Bookman, Ebony and Best, Lyle G and Bella, Jonathan N and Eaton, Charles and Greenland, Philip and Jenny, Nancy and North, Kari E and Taverna, Darin and Young, Alicia M and Deelman, Ewa and Kooperberg, Charles and Psaty, Bruce and Heiss, Gerardo} } @article {5863, title = {Genetic risk factors for ischaemic stroke and its subtypes (the METASTROKE collaboration): a meta-analysis of genome-wide association studies.}, journal = {Lancet Neurol}, volume = {11}, year = {2012}, month = {2012 Nov}, pages = {951-62}, abstract = {

BACKGROUND: Various genome-wide association studies (GWAS) have been done in ischaemic stroke, identifying a few loci associated with the disease, but sample sizes have been 3500 cases or less. We established the METASTROKE collaboration with the aim of validating associations from previous GWAS and identifying novel genetic associations through meta-analysis of GWAS datasets for ischaemic stroke and its subtypes.

METHODS: We meta-analysed data from 15 ischaemic stroke cohorts with a total of 12 389 individuals with ischaemic stroke and 62 004 controls, all of European ancestry. For the associations reaching genome-wide significance in METASTROKE, we did a further analysis, conditioning on the lead single nucleotide polymorphism in every associated region. Replication of novel suggestive signals was done in 13 347 cases and 29 083 controls.

FINDINGS: We verified previous associations for cardioembolic stroke near PITX2 (p=2{\textperiodcentered}8{\texttimes}10(-16)) and ZFHX3 (p=2{\textperiodcentered}28{\texttimes}10(-8)), and for large-vessel stroke at a 9p21 locus (p=3{\textperiodcentered}32{\texttimes}10(-5)) and HDAC9 (p=2{\textperiodcentered}03{\texttimes}10(-12)). Additionally, we verified that all associations were subtype specific. Conditional analysis in the three regions for which the associations reached genome-wide significance (PITX2, ZFHX3, and HDAC9) indicated that all the signal in each region could be attributed to one risk haplotype. We also identified 12 potentially novel loci at p<5{\texttimes}10(-6). However, we were unable to replicate any of these novel associations in the replication cohort.

INTERPRETATION: Our results show that, although genetic variants can be detected in patients with ischaemic stroke when compared with controls, all associations we were able to confirm are specific to a stroke subtype. This finding has two implications. First, to maximise success of genetic studies in ischaemic stroke, detailed stroke subtyping is required. Second, different genetic pathophysiological mechanisms seem to be associated with different stroke subtypes.

FUNDING: Wellcome Trust, UK Medical Research Council (MRC), Australian National and Medical Health Research Council, National Institutes of Health (NIH) including National Heart, Lung and Blood Institute (NHLBI), the National Institute on Aging (NIA), the National Human Genome Research Institute (NHGRI), and the National Institute of Neurological Disorders and Stroke (NINDS).

}, keywords = {Brain Ischemia, Databases, Genetic, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Risk Factors, Stroke}, issn = {1474-4465}, doi = {10.1016/S1474-4422(12)70234-X}, author = {Traylor, Matthew and Farrall, Martin and Holliday, Elizabeth G and Sudlow, Cathie and Hopewell, Jemma C and Cheng, Yu-Ching and Fornage, Myriam and Ikram, M Arfan and Malik, Rainer and Bevan, Steve and Thorsteinsdottir, Unnur and Nalls, Mike A and Longstreth, Wt and Wiggins, Kerri L and Yadav, Sunaina and Parati, Eugenio A and DeStefano, Anita L and Worrall, Bradford B and Kittner, Steven J and Khan, Muhammad Saleem and Reiner, Alex P and Helgadottir, Anna and Achterberg, Sefanja and Fernandez-Cadenas, Israel and Abboud, Sherine and Schmidt, Reinhold and Walters, Matthew and Chen, Wei-Min and Ringelstein, E Bernd and O{\textquoteright}Donnell, Martin and Ho, Weang Kee and Pera, Joanna and Lemmens, Robin and Norrving, Bo and Higgins, Peter and Benn, Marianne and Sale, Michele and Kuhlenb{\"a}umer, Gregor and Doney, Alexander S F and Vicente, Astrid M and Delavaran, Hossein and Algra, Ale and Davies, Gail and Oliveira, Sofia A and Palmer, Colin N A and Deary, Ian and Schmidt, Helena and Pandolfo, Massimo and Montaner, Joan and Carty, Cara and de Bakker, Paul I W and Kostulas, Konstantinos and Ferro, Jose M and van Zuydam, Natalie R and Valdimarsson, Einar and Nordestgaard, B{\o}rge G and Lindgren, Arne and Thijs, Vincent and Slowik, Agnieszka and Saleheen, Danish and Par{\'e}, Guillaume and Berger, Klaus and Thorleifsson, Gudmar and Hofman, Albert and Mosley, Thomas H and Mitchell, Braxton D and Furie, Karen and Clarke, Robert and Levi, Christopher and Seshadri, Sudha and Gschwendtner, Andreas and Boncoraglio, Giorgio B and Sharma, Pankaj and Bis, Joshua C and Gretarsdottir, Solveig and Psaty, Bruce M and Rothwell, Peter M and Rosand, Jonathan and Meschia, James F and Stefansson, Kari and Dichgans, Martin and Markus, Hugh S} } @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} }