T+31C polymorphism of angiotensinogen gene and essential hypertension

A common variant at codon 235 of the angiotensinogen gene with methionine t o threonine amino acid substitution (AGT M235T) has been reported as a gene tic risk for essential hypertension. However, the frequency of AGT T235 was heterogeneous among races, and a positive association between AGT M235T an d hypertension was not settled. To examine the association in a general pop ulation of Japanese (n = 4013), we introduced the TaqMan polymerase chain r eaction method and examined the relation between hypertension and T+31C pol ymorphism, which was in absolute linkage disequilibrium with AGT M235T. The C+31 allele of AGT was significantly associated with the positive family h istory of hypertension (FH) but not with the presence of hypertension or bl ood pressure. The subjects with CC tended to have hypertensive relatives, e specially a hypertensive father or siblings, and its statistical significan ce was stronger in men. Adjustment of confounding factor did not alter the results of simple association study, suggesting that this positive associat ion with FH is independent and significant. Our findings revealed that the TaqMan polymerase chain reaction method is a powerful tool for genetic asso ciation study with a large number of subjects and that AGT T+31C is signifi cantly associated with paternal FH.