Background: The angiotensin converting enzyme (ACE) is a key protein of the renin angiotensin system, whose main function is the conversion of angiotensin I to II. ACE is involved in the physiological control of blood pressure and it is a candidate gene for essential hypertension in humans. We tested the relevance of the ACE insertion/deletion (I/D) polymorphism in our population.
Methods: We recruited 243 hypertensive and 407 normotensive subjects in the city of Havana, matched according to age, sex and ethnic group. The ACE (I/D) polymorphism was determined by the polymerase chain reaction (PCR) technique. The fit of genotype frequencies to Hardy-Weinberg proportions was evaluated in all groups analyzed. The possible association between the ACE I/D polymorphism and hypertension status was tested by chi2 and odds ratio tests.
Results: All groups but black female cases were in Hardy-Weinberg equilibrium. The frequencies of the D allele in hypertensive/normotensive subjects were 0.61/0.59 in white males, 0.58/0.58 in white females, 0.47/0.59 in black males and 0.58/0.54 in black females. The distribution of ACE genotypes differed significantly between cases and controls only in black women according to the additive model (chi2p=0.04) but the adjusted OR did not show significant association (OR 1.14 95% CI 0.62 to 2.10).
Conclusion: The ACE I/D polymorphism was not associated with hypertension in our multiethnic sample. While the chi2 test for additive model in black women suggested a marginal significance, the adjusted OR did not show any significant association.