Utility of blood pressure genetic risk score in admixed Hispanic samples

Hypertension is strongly influenced by genetic factors. Although hypertension prevalence in some Hispanic sub-populations is greater than in non-Hispanic whites, genetic studies on hypertension have focused primarily on samples of European descent. A recent meta-analysis of 200 000 individuals of European descent identified 29 common genetic variants that influence blood pressure, and a genetic risk score derived from the 29 variants has been proposed. We sought to evaluate the utility of this genetic risk score in Hispanics. The sample set consists of 1994 Hispanics from 2 cohorts: the Northern Manhattan Study (primarily Dominican/Puerto Rican) and the Miami Cardiovascular Registry (primarily Cuban/South American). Risk scores for systolic and diastolic blood pressure were computed as a weighted sum of the risk alleles, with the regression coefficients reported in the European meta-analysis used as weights. Association of risk score with blood pressure was tested within each cohort, adjusting for age, age(2), sex and body mass index. Results were combined using an inverse-variance meta-analysis. The risk score was significantly associated with blood pressure in our combined sample (P = 5.65 x 10(-4) for systolic and P = 1.65 x 10(-3) for diastolic) but the magnitude of the effect sizes varied by degree of European, African and Native American admixture. Further studies among other Hispanic sub-populations are needed to elucidate the role of these 29 variants and identify additional genetic and environmental factors contributing to blood pressure variability in Hispanics.