To assess the association of SstI gene polymorphism (3238 C to G substitution) in Apolipoprotein CIII gene with coronary artery disease (CAD) among North Indians.Background
The plasma concentration of apolipoprotein (apo) C-III is a strong predictor of the risk of coronary heart disease. Genetic variation affecting the expression of the APOC3 gene may alter apoC-III metabolism and may influence occurrence of CAD. Minor alleles of the 3238 C to G (SstI site) polymorphism have traditionally been associated with higher plasma triglycerides, higher apoC-III concentrations and with an increased risk of CAD.Methods
We prospectively included 200 consecutive angiographically proven CAD patients and the same number of disease free, healthy controls. The patient and controls were ethnically matched and were residents of North India. Genotyping of the patients and controls was done using standard polymerase chain reaction-restriction fragment length polymorphism(PCR-RFLP) assay.Results
Baseline characteristics and risk factor distribution including history of diabetes, hypertension, smoking, family history of CAD and mean levels of serum lipids were found to be significantly higher in patients than in controls (p < 0.001). We found no significant association of Sstl polymorphism with CAD when we compared the various genotype/allele frequencies in patients and controls (p > 0.05). We were not able to find any association of this polymorphism with CAD even after employing additive, dominant and recessive genetic models indicating no association whatsoever with CAD. No association of this gene polymorphism was seen, even in the mean levels of serum triglyceride values in patients versus controls, possible reason of the same could be that a most of the patients were on lipid lowering medications (at the time of inclusion) as opposed to only a few in the control group which possibly affected the results.Conclusion
Our results suggest that unlike several ethnic populations around the world, North Indians have no or limited association of Apo CIII-SstI polymorphism with CAD.