A common variant of the ABO gene protects against hypertension in a Spanish population.

The objective of this study was to establish whether genetic polymorphisms that could be related to angiotensin-converting enzyme (ACE) levels are associated with hypertension. A total of 10 haplotype-tagging single-nucleotide polymorphisms in ACE, the ACE I/D polymorphism, and 2 polymorphisms in the ABO (rs495828 and rs8176746) were investigated for association with hypertension in 269 hypertensive patients and 254 healthy controls. All analyses were adjusted for age and body mass index, and corrected for multiple testing. Only one polymorphism of the ABO gene (rs495828) presented nominal pointwise P<0.05 values (odds ratio = 0.33, 95% CI 0.19-0.58, P = 6 × 10(-5)) and achieved P<3.8 × 10(-3), the nominal P-value considered significant after Bonferroni correction. Analysis of the genotype frequencies showed that the model that correctly explained the observed association was the recessive model (odds ratio = 0.03, 95% CI 0.01-0.15, P = 1 × 10(-6)). These results indicate that genetic variants that could be related to ACE activity are good predictors of hypertension, and identify ABO as a good candidate gene for genetic studies of hypertension risk. Further studies are required to confirm this association.