Analysis of apolipoprotein E genetic polymorphism in a large ethnic Hakka population in southern China

There is currently no data about the genetic variations of APOE in Hakka population in China. The aim of this study was to analyze the allelic and genotypic frequencies of APOE gene polymorphisms in a large ethnic Hakka population in southern China. The APOE genes of 6,907 subjects were genotyped by the gene chip platform. The allele and genotype frequencies were analyzed. Results showed that the epsilon 3 allele had the greatest frequency (0.804) followed by epsilon 2 (0.102), and epsilon 4 (0.094), while genotype epsilon 3/epsilon 3 accounted for 65.43% followed by epsilon 2/epsilon 3 (15.85%), epsilon 3/epsilon 4 (14.13%), epsilon 2/epsilon 4 (3.01%), epsilon 4/epsilon 4 (0.84%), and epsilon 2/epsilon 2 (0.74%) in all subjects. The frequencies of the epsilon 4 allele in Chinese populations were lower than Mongolian and Javanese, while the frequencies of the epsilon 2 allele were higher and epsilon 4 allele lower than Japanese, Koreans, and Iranian compared with the geographically neighboring countries. The frequencies of epsilon 2 and epsilon 4 alleles in Hakka population were similar to the Vietnamese, Chinese-Shanghai, Chinese-Kunming Han and Chinese-Northeast, and French. The frequency of epsilon 2 in Hakka population was higher than Chinese-Dehong Dai and Chinese-Jinangsu Han. The low frequency of the APOE epsilon 4 allele may suggest a low genetic risk of Hakka population for cardiovascular disease, Alzheimer's disease, and other diseases.