Angiotensinogen M235T variant and salt sensitivity in young normotensive caucasians

Background and aims A single-nucleotide variant of the angiotensinogen gene (AGT 235T) has been associated with essential hypertension and increased p lasma levels of angiotensinogen, This variant may also serve as a genetic m arker for the increased blood pressure response to dietary salt intake, but the relationship between AGT genotype and salt sensitivity has not been st udied until now. We therefore examined the relationship between the AGT 235 T genotype and the blood pressure response to short-term dietary salt restr iction in young normotensive men. Subjects and methods A total of 187 young normotensive men were characteriz ed for family history of hypertension, salt sensitivity, plasma parameters of the renin-angiotensin system under high- and low-salt diets, and the AGT 235T genotype, Results While the T allele was significantly associated with a positive fam ily history of hypertension (chi(2) = 7.0; P < 0.03) and higher plasma angi otensinogen levels (P < 0.015) and renin activity (P < 0.037), blood pressu re under both diets was not significantly affected by the AGT genotype, Whe n the subjects were classified into salt-resistant and salt-sensitive group s, genotypic distribution was nearly identical between both groups (frequen cy of T allele: 0.45 versus 0.46). Conclusion Our findings demonstrate that the AGT 235T allele is significant ly associated with a positive family history of hypertension, but is not an important determinant of the blood pressure response to dietary salt intak e in young normotensive subjects, It is therefore unlikely that the AGT 235 T genotype can serve as an early genetic marker of salt sensitivity. J Hype rtens 1999, 17:475-479 (C) Lippincott Williams & Wilkins.