title: Genetic variation in soluble epoxide hydrolase (EPHX2) and risk of coronary heart disease: The Atherosclerosis Risk in Communities (ARIC) study.
abstract: Endothelial dysfunction contributes to the development of coronary heart disease (CHD). Soluble epoxide hydrolase metabolizes epoxyeicosatrienoic acids in the vasculature and regulates endothelial function. We sought to determine whether genetic variation in soluble epoxide hydrolase (EPHX2) was associated with the risk of CHD. We genotyped 2,065 Atherosclerosis Risk in Communities study participants (1,085 incident CHD cases, 980 non-cases) for 10 previously identified polymorphisms in EPHX2. Using a case-cohort design, associations between incident CHD risk and both non-synonymous EPHX2 polymorphisms and phase-reconstructed haplotypes were evaluated using proportional hazards regression. Individuals carrying the K55R polymorphism variant allele demonstrated higher apparent soluble epoxide hydrolase activity in vivo. Presence of the K55R variant allele was significantly more common among Caucasian CHD cases when compared with non-cases (20.8% versus 15.3%, respectively, P=0.012), and was associated with significantly higher risk of incident CHD (adjusted hazard rate ratio 1.45, 95% confidence interval 1.05-2.01, P=0.026). A significant association between the K55R variant allele and risk of CHD was not observed in African-Americans. The distribution of reconstructed haplotypes were significantly different in Caucasian cases when compared with non-cases (P=0.021). Significant differences in haplotype distribution were not observed in African-Americans (P=0.315). Genetic variation in EPHX2 was significantly associated with risk of incident CHD in Caucasians, implicating EPHX2 as a potential cardiovascular disease-susceptibility gene.
authors.affiliation: Division of Intramural Research, National Institute of Environmental Health Sciences, National Institutes of Health Research, Triangle Park, NC 27709, USA.
authors.forename: Craig R
authors.initials: CR
authors.lastname: Lee
authors.forename: Kari E
authors.initials: KE
authors.lastname: North
authors.forename: Molly S
authors.initials: MS
authors.lastname: Bray
authors.forename: Myriam
authors.initials: M
authors.lastname: Fornage
authors.forename: John M
authors.initials: JM
authors.lastname: Seubert
authors.forename: John W
authors.initials: JW
authors.lastname: Newman
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Hammock
authors.forename: David J
authors.initials: DJ
authors.lastname: Couper
authors.forename: Gerardo
authors.initials: G
authors.lastname: Heiss
authors.forename: Darryl C
authors.initials: DC
authors.lastname: Zeldin
mesh_terms: D001741:Black or African American; D003327:Coronary Disease / Q000208:ethnology / Q000209:etiology / Q000235:genetics*; D004851:Epoxide Hydrolases / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D014644:Genetic Variation; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D012306:Risk; D012907:Smoking / Q000009:adverse effects; D044465:White People
chemical_list: D004851:Epoxide Hydrolases; C506428:EPHX2 protein, human