Apolipoprotein E and angiotensin-converting enzyme gene polymorphisms as risk factors of coronary disease
Bennouar, N.; Allami, A.; Laraqui, A.; Azeddoug, H.; El-Kadiri, N.; Benkouka, F.; Bendriss, A.; Ghannam, R.; Benomar, A.; Fellat, S.; Benomar, M.
Annales de Biologie Clinique 62(3): 295-304
2004
ISSN/ISBN: 0003-3898 PMID: 15217762 Document Number: 569272
The objective of this study was to test the hypothesis that apo E (RFLP, Hhal) and/or angiotensin-converting enzyme (ACE) (ins16del) are associated with higher risk for coronary heart disease. We investigated 250 patients who underwent complete cardiac examination comprising coronary angioplasty and biological analysis (CT, HDLc, LDLc, TG, apo A and apo B). Prevalence of the alleles of apo E and ACE was assessed by molecular analysis. Patients without stenosis or with non-significant stenosis (< 50% of the vascular lumen) were used as reference group (141 patients). Those presenting a : significant stenosis of the coronary artery ( gtoreq 50% of the vascular lumen) were considered as cases (109 patients). The relative frequency of the epsilon4 allele was significantly higher in cases than in reference group (p < 0.02). A strong association have been found between coronary heart disease and apo E polymorphism (chi2 = 8.91; p < 0.05). The presence of the epsilon4 allele increase the risk of atherosclerosis (RR = 2.71; IC95%: 1.25-5.90; p < 0.02) compared to epsilon3 allele. Also, subjects with D allele were more frequent in cases than in reference group (p < 0.001). A significant association was noted between ACE polymorphism and coronary heart disease (chi2 = 42.15; p < 0.001). This relationship was positive (rho de Spearman = 0.39; p < 0.01). With D/D homozygotes patients, the RR for coronary heart disease was 19.10 (p < 0.001), while The RR with I/D heterozygotes was 6.91 (p < 0.001) compared to I/I homozygotes. A significant interaction have been shown up between D/D genotype and arterial hypertension (HTA) (chi2 de Wald = 16. 10; p < 0.001). The multivariate analysis showed that the chronic smoking, diabetes, hypoapolipoproteinemia A, interactive effects between D/D and HTA, I/D and obesity, and between D/D and hypertriglyceridemia were the major significant factors to take into consideration in our population. We also note that subjects with both D and epsilon4 alleles were presenting a high risk to coronary heart disease (RR = 5.93; IC95%: 2.00-17.55; p < 0.01). Thus, those two alleles (epsilon4 and D) appears to be important cardiovascular risk factors in the moroccan population.