Association of a DNA polymorphism of the apolipoprotein AI-CIII-AIV gene cluster with myocardial infarction in a Tunisian population.

Background: Apolipoproteins AI-CIII-AIV play important roles in the metabolism of triglycerides and high-density lipoprotein cholesterol. However, whether genetic variations in the ApoAI-CIII-AIV gene cluster are associated with the risk of myocardial infarction (MI) remains uncertain. In the present study, we examined a possible association of the ApoCIII SacI polymorphism in the ApoAI-CIII-AIV gene cluster with lipid parameters and MI in a sample of the Tunisian population.

Methods: A total of 326 Tunisian patients with MI and 361 controls were included in the study. Genotypes were determined by polymerase chain reaction--restriction fragment length polymorphism (PCR-RFLP) analysis.

Results: A significant difference in genotype distribution and allele frequency was observed between patients and controls. At the multivariate analysis after adjustment for traditional vascular risk factors, the ApoCIII SacI polymorphism was significantly associated with MI, according to co-dominant and dominant models (co-dominant model odds ratio [OR]: 1.53, 95% confidence interval [CI]: 1.0-2.35, p=0.04; dominant model OR: 2.02, 95% CI: 1.11-3.67, p=0.02). The MI patient group showed a significant higher frequency of the S2 allele compared to the controls (10.2% vs. 6.5%; OR: 1.64, 95% CI: 1.10-2.47, p=0.01). There was no statistically significant association between ApoAI-CIII-AIV cluster gene polymorphism and lipid, lipoprotein, and apolipoprotein levels in both MI patients and controls.

Conclusion: In the current study, a significant association between the ApoCIII SacI polymorphism (presence of S2 allele) and MI in the Tunisian population was found.