Apolipoprotein E gene polymorphism in the mongolian population

Apolipoprotein E plays a key role in the regulation of lipid metabolism. ApoE function is determined by the presence of three common alleles (epsilon 2, epsilon 3, epsilon 4). The apo epsilon 3 allele is the most prevalent, apo epsilon 2 is associated with dysbetalipoproteinaemia, and apo epsilon 4 is frequently associated with an increased risk for cardiovascular and Alzheimer's diseases. Mongolian population has a high rate of cardiovascular mortality and morbidity and there might be genetic susceptibility of the population to cardiovascular disease. The aim of our study was to establish the frequency of apoE genotypes in 744 Mongolian subjects and to compare the results with findings from other Asian populations. The apo E sequence was amplified using polymerase chain reaction and apo E genotyping was performed by restriction enzyme cleavage with CfoI. The relative apoE allele frequencies were epsilon 2 = 3.7%, epsilon 3 = 80.8%, and epsilon 4 = 15.5%, the genotype frequencies were epsilon 2/epsilon 2 = 0% (N = 0), epsilon/2 epsilon 3 = 5.7% (N = 42), epsilon 2/epsilon 3 = 1.7% (N = 13), epsilon 3/epsilon 4 65.3% (N = 486), epsilon 3/epsilon 4 = 25.4% (N = 189), epsilon 4/epsilon 4 1.9% (N = 14); the occurrence of the risk epsilon 4 allele in Mongolia is among the highest in Asia. The high frequency of the apo epsilon 4 allele may increase the susceptibility of Mongolian population to cardiovascular diseases.