Apolipoprotein-E Gene Isoforms Genetic Spectrum in Pakistani Survivors of Myocardial Infarction

Apolipoprotein E (APOE) gene have two common polymorphic risk alleles APOE112 and AP0158 which constitute six isoforms categorized in three genotypes E2 (8282, s2c3, s264), E3 (s3s3) and E4 (8364, 8484). We aimed to assess APOE genotypes association with myocardial infarction in Pakistani cohort. Serum lipid levels were determined of survivors of myocardial infarction (n=100) and control (n=100) and genotyped using high throughput fluorescence based TaqMan and KASPar assays. The APOE158 risk allele frequency was significantly lower in diseased (p -value 0.025). Three alleles E2 (15%), E3 (71%), E4 (14%) and E2 (5%), E3 (76%), E4 (18%) were observed among control and MI patients respectively. The E2 genotype found significantly lower for total cholesterol compared to E3 (p-value=0.013) and E4 (p-value=0.006). LDL-cholesterol values of E2 genotypes were also significantly lower to E3 (p-value=0.002), E4 (p-value=0.009) and triglycerides levels (p-value=0.039) to E4. The isoform epsilon 3 epsilon 3 is more common among Pakistani population and genotype E2 can be considered as lipid lowering and piotective. These findings conclude that APOE isoforms have genetic contribution with lipid levels and cardiovascular disease in Pakistan patients.