Apoprotein-E gene polymorphism in an Iraqi population with type 2 diabetes and cardiovascular disease

Abstract

Introduction and Aim: The ApoE gene polymorphisms are considered as risk factors for developing atherosclerosis and related cardiovascular disease (CVD) in humans. There exists no study pertaining to ApoE gene polymorphism and its association to these disorders among the Iraqi population. Hence in this study, we aimed to investigate the possible relationship between single nucleotide polymorphisms (SNPs) in the ApoE gene with the prevalence of diabetes (T2DM) and cardiovascular disease among the Iraqi population. Materials and Methods: This cross-sectional investigation involved 76 patients (50 with diabetics and 26 with cardiovascular disease) and 73 otherwise healthy individuals. The ApoE gene fragment corresponding to the SNPs rs429358 and rs7412 was amplified using conventional polymerase chain reaction (PCR) with a specific pair of primers. Genotyping was performed by direct sequencing. Results: Differences in genotypic and allelic frequencies were seen in SNPs rs429358 and rs7412 of the ApoE gene. Significant higher frequency was seen for the CT genotype in SNP rs429358 when compared to healthy controls. Among the epsilon alleles, the E3/E3 was the most common genotype, accounting for 76% and 69.23% of patients with diabetes and CVD, respectively. E2/E4 was the least common genotype, accounting for 2% and 0% of diabetes and CVD patients, respectively. When DM patients were compared to controls, the genotype E 3 E 4 was found to be more common in T2DM patients (10%) than in controls (1.34%), with a significant difference (OR= 4.32, 95%CI=0.02-0.98, p= 0.050). At the allelic level, the E2 allele was significantly more common in patients than in controls (OR= 12.73, 95%CI= 1.38-116.87). Conclusion: Data in this study indicate ApoE gene polymorphisms in SNPs rs429358 and rs7412 could be risk factors for T2DM and CVD in Iraqi patients.