ASSOCIATION BETWEEN ANGIOTENSIN-CONVERTING ENZYME GENE POLYMORPHISM AND CAROTID ATHEROSCLEROSIS

Objective Variations in the angiotensin converting enzyme (ACE) gene h ave been implicated in cardiovascular pathology, Therefore, the associ ation between the intima-media thickness (IMT) of the carotid artery a nd the insertion/deletion (I/D) polymorphism of the ACE gene was inves tigated. Subjects Three hundred men and 300 women were selected random ly from the middle-aged population living in the town Oulu, Finland, o f whom 515 subjects (85.8%) participated, Methods The IMT of the carot id arteries was determined by bilateral B-mode ultrasonography. IMT va lues were adjusted for gender, age, height, plasma low-density lipopro tein cholesterol level, smoking and systolic blood pressure. The I/D p olymorphism of the ACE gene was determined by polymerase chain reactio n. Results Among non-smokers, the subjects with the DD genotype had si gnificantly higher carotid IMT than did those with II or ID, The assoc iation was found also in combined IMT plaque values, In the total popu lation the association was weaker and it was absent in current smokers , Genotype could explain 1.3-2.7% of the variance of carotid IMT in no n-smokers. No association between the amount or size of carotid plaque s and genotype was observed. Conclusions Variations at the ACE gene lo cus contribute to the deg ree of the early changes in carotid atherosc lerosis in the population, The gene effect is, however, masked by stro nger effects of environmental factors such as smoking, The lack of ass ociation between atherosclerotic plaques and genotypes may reflect dif ferent mechanisms being involved in plaque development and early arter ial wall thickening.