Correlation of apolipoprotein E gene polymorphism to serum lipid concentrations in healthy Thais

This study determined the genotype distribution of apolipoprotein E (apo E) gene and its relation to serum lipids in 217 healthy Thais consisting of 79 males and 138 females. Serum total cholesterol (TC), HDL-cholesterol (HDL-C) and triglyceride (TG) concentrations were determined by enzymatic-colorimetric methods, while serum LDL-cholesterol (LDL-C) levels were calculated using Friedewald formula. Apo E genotypes were determined by PCR-RFLP. Out of 217 subjects, apo E genotype frequencies were 5.5 per cent for E2/E2, 12.4 per cent for E2/E3, 81.1 per cent for E3/E3 and 0.9 per cent for E4/E4. In men, advancing age was associated with increased serum TC (r = 0.28, P < 0.05) and LDL-C (r = 0.27, P < 0.01). Subjects having the E2 allele had lower TC (r = -0.27, P < 0.05) and LDL-C. (r = -0.25, P < 0.05). Age and apo E genotypes were not associated with HDL-C and TG in men. In women, increasing age was related to higher serum TC (r = 0.45, P < 0.001), LDL-C (r = 0.44, P < 0.001), TG (r = 0.40, P < 0.001) and lower HDL-C (r = -0.36, P < 0.001). The presence of E2 allele was related to lower TC (r = -0.24, P < 0.001), LDL-C (r = -0.26, P < 0.001), TG (r = -0.15, P < 0.05) and higher HDL-C (r = 0.20, P < 0.01) independent of age and menopausal status. We concluded that the epsilon 4 allele of apo E gene is rare in Thais. The presence of the epsilon 2 allele is associated with a more favorable lipid profile and there is a sexual dimorphism concerning the effect of apo E genotype on serum HDL-C and TG.