A complex association of ABCA7 genotypes with sporadic Alzheimer disease in Chinese Han population.

Purpose: Recently, a large genome-wide association study has revealed that polymorphism of alleles and genotypes in rs3,764,650 within ABCA7 gene is associated with Alzheimer disease in whites. We conducted a case-control study to investigate whether these susceptible genetic variants are risk factors for sporadic Alzheimer disease (SAD) in Chinese Han population.

Design And Methods: A total of 633 participants consisting of 350 SAD and 283 nondemented elderly controls matched for sex and age were recruited and genetic variants in ABCA7 (rs3,764,650) were genotyped using DNA sequencing.

Results: On the basis of allele and genotype frequencies in both groups, we found a significant association (P=0.004) between ABCA7 genotypes and SAD in Chinese Han population, and the results were influenced by age and ApoEε4 status. ApoEε4-carrier and aging are linked to enhancing ABCA7 risk-associated SAD. However, the prevalence of the minor allele G in rs3,764,650 within ABCA7 showed no significant difference between the 2 groups in this study.

Conclusions: ABCA7 (rs3,764,650) was associated with SAD in the Chinese population, with both ApoEε4-carrier and aging being factors enhancing its risk.