Estudo sobre aspectos genéticos da Hipertensão Arterial Sistêmica em Afro descendentes do sudoeste do estado da Bahia

Abstract

Hypertension (HBP) is a common and multifactorial disease. The Renin Angiotensin System (RAS) has close relationship with the process of hypertension. The aim of this study was to investigate the association of RAS polymorphisms following: the M235T angiotensinogen (AGT), the C-344T aldosterone synthase (CYP11B2), A1166C in Receptor Type 1 Angiotensin II (AT1R), I/D in-Converting Enzyme (ACE) and G2646A in Renin (REN) with hypertension in a sample of 505 individuals of African descent of Bahia state. The amplification of the sample was done with polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP). The results shown that the frequency of the 235T allele in AGT was higher in hypertensive (60%), compared to normotensive (53%, p = 0.05). The frequency of -344T allele in CYP11B2 was also higher in hypertensive (63%) compared to normotensive (54%, p = 0.006). Otherwise, there were no significant differences in the frequencies of A1166C polymorphisms in the AT1R, I/D ACE and G2646A in the REN between hypertensive and normotensive Afro-descendants. A logistic regression analysis showed that individuals homozygous for the AGT 235T allele had a risk about 1.8 times more likely to have hypertension (odds ratio = 1.848, p = 0.013) when compared with carriers of the allele 235M, and the homozygous 235TT genotype in the AGT gene is associated with an increased risk of hypertension among Afro-descendants. All other polymorphisms studied, including the C-344T i CYP11B2 did not remain as significant predictors of risk for hypertension, and, were not associated with hypertension among African-Americans.