Association between apolipoprotein E gene polymorphism and Alzheimer's disease in Uighur and Han populations.

Aim: Currently, there are almost 100 genes related to Alzheimer's disease (AD), and studies have indicated that apolipoprotein E (APO E) ε4 allele is a genetic risk factor of AD. However, there have been no reports of the distributions of APO E genotypes and allele frequencies in Uighur and Han AD patients.

Methods: We analyzed APO E gene polymorphism in 209 AD cases diagnosed based on National Institute of Neurological and Communicative Disorders and Stroke and Alzheimer's Disease and Related Disorders Association and 220 non-dementia controls. We used polymerase chain reaction-restriction fragment length polymorphism methods as the basis of this epidemiological survey.

Results: In the AD and control groups, there are no statistically significant differences in APO E genotypes and allele frequency between the Uighur and Han ethnicities (P < 0.05). In the AD group, the ε3/4 genotype (28.2%) and ε4 allele frequency (14.8%) occurred at a higher rate than in the control (13.2% and 8.0%, respectively; P < 0.05). This distinction remained true within each ethnicity; the ε3/4 genotype and ε4 allele frequency are higher in the AD groups (Uighur, 30.6% and 15.8%, respectively; Han, 25.5% and 13.8%, respectively) than in the control groups (Uighur, 14.5% and 9.4%, respectively; Han, 11.7% and 6.3%, respectively; P < 0.05).

Conclusions: The distribution of APO E genotype and allele frequency does not differ between the Uighur and Han ethnicities. The APO E ε4 allele is a risk factor of AD for both populations.