Lack of evidence for an association between α-adducin and blood pressure regulation in Asian populations

Recent studies have found the tryptophan allele of a glycine to tryptophan polymorphism at position 460 (G460W) of the α-adducin protein to be associated with essential hypertension in European populations. We examined whether the tryptophan allele is associated with hypertension in a different population, comprised of subjects of Chinese origin from Taiwan, and Chinese and Japanese origin from the San Francisco Bay area and Hawaii. We adapted the 5′ allelic discrimination assay or TaqMan to type individuals for the G460W polymorphism, and using this method we typed more than 1000 individuals. The frequency of the W allele was slightly increased in the treated subjects in the Chinese population (0.458 v 0.423) but not the Japanese population (0.549 v0.558). We considered dominant, recessive, and additive models in our analysis. There was a significant result for a recessive model for systolic blood pressure in the Chinese population (χ2 6.84, df = 2, P< .05), but only suggestive evidence for diastolic blood pressure (χ2 3.30). In contrast, in the Japanese population, there was no evidence for a positive association under any model. For the combined Chinese and Japanese samples, the evidence for association with α-adducin was not significant.