AGT and RH blood group polymorphisms affect blood pressure and lipids in Afro-Caribbeans

Abstract

Population blood pressure variation is most likely due to multiple genes. This is likely the reason why monogenic testing with the angiotensinogen (AGT) gene polymorphisms on chromosome 1 (1q42-43), especially M235T, has met with negative results, especially in those of African descent. The RH blood group system, also on chromosome 1 (1 p36.2-34), has likewise been associated with blood pressure variation in AfricanAmericans and with the rise in blood pressure with age in whites. Using a random sample of the population, we investigated the combined effects of single and combined variation of the AGTN M235T and RH genotypes on blood pressure, lipids, and lipoprotein concentrations in Afro-Caribbeans aged 18-60 years from the island nation of Dominica. In monogenic analysis, AGT M235T was not associated with blood pressure. However, it was associated with HDL (MM 42723, MT 44712, TT 52714 (P ¼ 0.002)). RH genotype was significantly associated with systolic blood pressure (P ¼ 0.006) and Apo-A (P ¼ 0.003). These effects remained after adjustment for age, gender, weight, and BMI. In the polygenetic analysis, AGT M235T and RH were significantly associated with systolic blood pressure (P ¼ 0.037; interaction effects, P ¼ 0.068). The association of the AGT M235T with blood pressure across RH blood group haplotypes was then tested. Of the five RH haplotypes available for analysis, the AGT M235T was significantly associated with blood pressure within the ''D'' haplotype (P ¼ 0.01). The RH blood group and gender were significantly associated with systolic blood pressure and Apo-A levels (P ¼ 0.005 and 0.012, respectively). All interactions were independent of age and weight. In conclusion, we demonstrate a significant association of AGT M235T with blood pressure and cholesterol metabolism in an Afro-Caribbean population in the ''genetic context'' of the RH blood group system. Further investigation of these interactions may help understand the effects of genetic factors on cardiovascular risk in African-derived and other populations.

Association of blood groups with prognosis in acute coronary syndrome

“…Our study reported all-cause mortality of 22.07% in non-O group compared with that of 17.19% in the O group during a 7-year follow-up, but it was not statistically of Apo-A, which remained significant after adjustment for age, sex, weight, and body mass index in Afro-Caribbeans. 25 In our study, hypertension was an independent correlate of 7-year mortality, but the presence of hypertension did not differ significantly between Rh+ and Rh-patients at the time of ACS (P = 0.89). Our study showed that the Rh-positive factor may be a new potential factor in the global risk assessment in patients with ACS during long-term follow-up.…”

Structure, function and significance of Rh proteins in red cells

“…Apart from HDFN, no relationship between the major polymorphic Rh antigens and the susceptibility to infectious disease, neoplasms or other diseases has emerged [27]. There are hints of linkage between Rh blood group and blood pressure or cholesterol metabolism or both [28]. A recent study reports increased incidence of bilary complications in transplant recipients of livers mismatched for RhD [29].…”

Effects of Angiotensinogen and Angiotensin II Type I Receptor Genes on Blood Pressure and Left Ventricular Mass Trajectories in Multiethnic Youth

“…Tiago et al (2003) aged 51 (± 11) years who had never received therapy. A study of Afro-Caribbeans aged between 18 and 60 years by Robinson et al (2004) observed that M235T was significantly associated with blood pressure only within one specific Rh blood group. The study by Province et al (2000) which assessed the effect of the G-6A polymorphism on BP in the NHLBI family blood pressure program was the only study that involved both EAs and AAs and did observe 6G allele carriers had significantly lower levels of both SBP and DBP in AAs of one network group (HyperGen), although the meta-analysis based on the total of four network groups did not reach significance.…”