title: DRD2 C957T and TaqIA genotyping reveals gender effects and unique low-risk and high-risk genotypes in alcohol dependence.
abstract: OBJECTIVE
  As recent conflicting reports describe a genetic association between both the C- and the T-alleles of the dopamine D2 receptor (DRD2) C957T polymorphism (rs6277) in alcohol-dependent subjects, our aim was to examine this polymorphism and TaqIA (rs1800497) in Australian alcohol-dependent subjects.
  
  
  METHODS
  The C957T polymorphism was genotyped in 228 patients with alcohol dependence (72 females and 156 males) and 228 healthy controls.
  
  
  RESULTS
  The C-allele and C/C genotype of C957T was associated with alcohol dependence, whereas the TaqIA polymorphism was not. When analysed separately for C957T, males showed an even stronger association with the C-allele and females showed no association. The C957T and TaqIA haplotyping revealed a strong association with alcohol dependence and a double-genotype analysis (combining C957T and TaqIA genotypes) revealed that the relative risk of different genotypes varied by up to 27-fold with the TT/A1A2 having an 8.5-fold lower risk of alcohol dependence than other genotypes.
  
  
  CONCLUSIONS
  Decreased DRD2 binding associated with the C-allele of the DRD2 C957T polymorphism is likely to be important in the underlying pathophysiology of at least some forms of alcohol dependence, and this effect appears to be limited to males only.
authors.affiliation: Institute of Health and Biomedical Innovation, Queensland University of Technology, 60 Musk Ave., Kelvin Grove, Queensland 4059, Australia.
authors.forename: Christopher D
authors.initials: CD
authors.lastname: Swagell
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Lawford
authors.forename: Ian P
authors.initials: IP
authors.lastname: Hughes
authors.forename: Joanne
authors.initials: J
authors.lastname: Voisey
authors.forename: Gerald F X
authors.initials: GF
authors.lastname: Feeney
authors.forename: Angela
authors.initials: A
authors.lastname: van Daal
authors.forename: Jason P
authors.initials: JP
authors.lastname: Connor
authors.forename: Ernest P
authors.initials: EP
authors.lastname: Noble
authors.forename: C Phillip
authors.initials: CP
authors.lastname: Morris
authors.forename: Ross McD
authors.initials: RM
authors.lastname: Young
mesh_terms: D000328:Adult; D000368:Aged; D000437:Alcoholism / Q000235:genetics*; D000483:Alleles; D001315:Australia; D016022:Case-Control Studies; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D012306:Risk; D012737:Sex Factors
chemical_list: D017448:Receptors, Dopamine D2