5' ins/del and 3' VNTR polymorphisms in the apolipoprotein B gene in relation to lipids and coronary artery disease

Abstract

Background: Studies that considered apolipoprotein B (APOB) gene polymorphisms as risk factors for coronary artery disease (CAD) have reported conflicting results. We sought to analyze the association between 5' ins/del and 3' VNTR polymorphisms of APOB, lipid parameters and CAD risk.

Methods: We recruited 251 patients with CAD, documented by coronary angiography, and 94 controls. Genotyping was performed by PCR. Lipids and apolipoproteins were measured.

Results: 5' ins/del (ins/ins, ins/del, del/del) and 3' VNTR (LL, SS, LS) polymorphism frequencies were significantly (p<0.05) different between controls and CAD patients. LL and del/del were significantly associated with higher levels of apolipoprotein B (apoB), total cholesterol/high-density lipoprotein cholesterol ratio and apoB/apoA-I ratio (p<0.05) and with increased risk of CAD. The odds ratio for significant coronary stenosis associated with del/del was 3.2 (95% CI 1.6-36.42) (p=0.032) and with LL was 2.2 (95% CI 1.1-5.1) (p=0.042).

Conclusions: The two polymorphisms exert an impact on lipid levels and contribute to the susceptibility to the development of CAD.