Functional CLOCK gene rs1554483 G/C polymorphism is associated with susceptibility to Alzheimer's disease in the Chinese population

Abstract

Objective To examine the association between the circadian locomotor output cycles kaput ( CLOCK) gene rs1554483 G/C polymorphism and susceptibility to Alzheimer's disease in Chinese people. Methods This case–control study determined apolipoprotein E ( APOE) and CLOCK rs1554483 G/C genotypes using polymerase chain reaction restriction fragment length polymorphism. Results Unrelated patients with Alzheimer's disease ( n = 130) and healthy controls ( n = 188) were analysed for an association between the CLOCK gene rs1554483 G/C polymorphism and susceptibility to Alzheimer's disease. In the whole sample and in APOE ɛ4 isoform noncarriers, the prevalence of CLOCK gene rs1554483 G allele carriers was significantly higher in patients with Alzheimer's disease than in controls. Among APOE ɛ4 carriers, the prevalence of CLOCK rs1554483 G allele carriers was not significantly different between patients with Alzheimer's disease and controls. Conclusion Among APOE ɛ4 noncarriers, but not APOE ɛ4 carriers, the CLOCK rs1554483 G allele was associated with increased susceptibility to Alzheimer's disease.