ASSOCIATION OF A VARIABLE NUMBER OF TANDEM REPEATS IN THE ENDOTHELIALCONSTITUTIVE NITRIC-OXIDE SYNTHASE GENE WITH ESSENTIAL-HYPERTENSION IN JAPANESE

An impaired synthesis of nitric oxide (NO) by the vascular endothelium has been implicated in the pathogenesis of essential hypertension (EH ). The possible association between a variable number of tandem repeat s (VNTR) polymorphism in intron 4 of the endothelial constitutive NO s ynthase (ecNOS) gene and EH in Japanese subjects was investigated. A t otal of 123 individuals with EH and 120 normotensive control subjects were studied. The VNTR region of the ecNOS gene was amplified by the p olymerase chain reaction to determine the number of repeats, and the a llele frequencies were compared between the hypertensive and normotens ive groups. Two alleles, containing four and five repeats, were identi fied. The overall distributions of allele frequencies differed signifi cantly between the two groups, with the four-repeat allele more freque nt in the EH group than in the normotensive group (P = .00027, odds ra tio = 4.0). The four-repeat allele of the ecNOS gene was thus associat ed with EH and may be a genetic marker of this disease in Japanese sub jects. (C) 1998 American Journal of Hypertension, Ltd.