Impact of [Alpha]Enac Polymorphisms on the Risk of Ischemic Cerebrovascular Events: A Multicenter Case-Control Study (Molecular Diagnostics and Genetics‪)‬

Stroke represents one of the leading causes of morbidity and mortality in industrialized countries. Twin and family studies, together with observations in animal models, have shown that familial predisposition, in addition to established risk factors such as hypertension, smoking, diabetes, obesity, and age, contributes to the risk of stroke (1). Identification and characterization of gene variants that mediate this genetic predisposition may allow improved therapy and prevention (2-5). The role of individual mutations has been controversial. This is related in part to the fact that genetic influences in stroke are polygenic and that stroke comprises several different phenotypes. The effect of a genetic alteration may depend on a permissive background. The presence of a genetic variant could become phenotypically evident only in combination with modulating exogenous factors such as smoking, diet, or obesity, among others, and may increase the risk of disease. The results of epidemiologic and animal studies have indicated that genetic influences play a role in the pathogenesis of hypertension (6), which is the major risk factor for stroke. Amiloride-sensitive epithelial sodium channels (ENaCs) [5] are responsible for the rate-limiting step of sodium reabsorption in the distal nephron and are therefore important candidates in the development of hypertension. We evaluated the association of 2 common single-nucleotide polymorphisms (SNPs) in the [alpha]-subunit of the ENaC ([alpha]ENaC; SCNN1A; OMIM 600228) with ischemic cerebrovascular events (ICEs).