title: The polymorphism of CLOCK gene 3111T/C C>T is associated with susceptibility of Alzheimer disease in Chinese population.
abstract: OBJECTIVE
  In the present study, it was examined whether polymorphism of circadian locomotor output cycle kaput (CLOCK) gene 3111T/C was associated with susceptibility of Alzheimer disease (AD).
  
  
  METHODS
  This study was conducted using a case-control method. Genotypes of apolipoprotein E (APOE e4) and CLOCK gene 3111T/C were determined by restriction fragment length polymorphism method and TaqMan assay method, respectively.
  
  
  RESULTS
  In this study, we gathered 296 unrelated AD patients and 423 control subjects. Both in the whole sample and APOE e4 noncarriers, prevalence of C carriers in CLOCK gene 3111T/C in AD patients was significantly higher than that in control subjects (in the whole sample: χ = 37.615, P < 0.0001; in APOE e4 noncarriers: χ = 46.809, P < 0.0001). However, among APOE e4 carriers, prevalence of C carriers in CLOCK gene 3111T/C between patients and control subjects presents nonsignificant difference (χ = 0.812, P = 0.451).
  
  
  CONCLUSIONS
  Among APOE e4 noncarriers, C carriers in CLOCK gene 3111T/C were associated with a high susceptibility of AD, but among APOE e4 carriers, the functional polymorphism of CLOCK gene 3111T/C was not associated with the susceptibility of AD.
authors.affiliation: From the *Key Laboratory of Chronobiology of Health Ministry, Basic and Forensic School, Sichuan University, Chengdu; †Department of Oncology, The Affiliated Hospital of North Sichuan Medical College, Nanchong; and ‡Key Laboratory of Biological Effect of Physical Field and Instrument of Sichuan Provincial Department of Education and §Department of Electronic Engineering, Chengdu University of Information Technology, Chengdu, Sichuan; and ∥Department of Geriatrics, The Third Hospital of Mian Yang, Mian Yang, China.
authors.forename: Yun-Kang
authors.initials: YK
authors.lastname: Yang
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Peng
authors.forename: Yong-Hong
authors.initials: YH
authors.lastname: Li
authors.forename: Zheng-Rong
authors.initials: ZR
authors.lastname: Wang
authors.forename: Huang
authors.initials: H
authors.lastname: Chang-quan
authors.forename: Wang
authors.initials: W
authors.lastname: Hui
authors.forename: Qing-Xiu
authors.initials: QX
authors.lastname: Liu
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis* / Q000208:ethnology / Q000235:genetics*; D053327:Apolipoprotein E4 / Q000235:genetics; D044466:Asian People / Q000208:ethnology / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic / Q000235:genetics*; D011159:Population Surveillance / Q000379:methods*
chemical_list: D053327:Apolipoprotein E4