title: Lack of association of alcohol dependence and habitual smoking with catechol-O-methyltransferase.
abstract: OBJECTIVE
  To test whether variation in the gene encoding the enzyme catechol-O-methyltransferase (COMT), which catalyzes the breakdown of dopamine and other catecholamine neurotransmitters, is associated with the risk for alcohol dependence and habitual smoking.
  
  
  METHODS
  Single nucleotide polymophisms (SNPs) were genotyped in a sample of 219 multiplex alcohol-dependent families of European American descent from the Collaborative Study on the Genetics of Alcoholism (COGA). Family-based tests of association were performed to evaluate the evidence of association between the 18 SNPs distributed throughout COMT, including the functional Val158Met polymorphism, and the phenotypes of alcohol dependence, early onset alcohol dependence, habitual smoking, and comorbid alcohol dependence and habitual smoking.
  
  
  RESULTS
  No significant, consistent evidence of association was found with alcohol dependence, early onset alcohol dependence, habitual smoking or the comorbid phenotype. There was no evidence that the functional Val158Met polymorphism, previously reported to be associated with these phenotypes, was associated with any of them.
  
  
  CONCLUSIONS
  Despite the substantial size of this study, we did not find evidence to support an association between alcohol dependence or habitual smoking and variation in COMT.
authors.affiliation: Indiana University School of Medicine, Indianapolis, Indiana 46202-3002, USA. tforoud@iupui.edu
authors.forename: Tatiana
authors.initials: T
authors.lastname: Foroud
authors.forename: Leah Flury
authors.initials: LF
authors.lastname: Wetherill
authors.forename: Danielle M
authors.initials: DM
authors.lastname: Dick
authors.forename: Victor
authors.initials: V
authors.lastname: Hesselbrock
authors.forename: John I
authors.initials: JI
authors.lastname: Nurnberger
authors.forename: John
authors.initials: J
authors.lastname: Kramer
authors.forename: Jay
authors.initials: J
authors.lastname: Tischfield
authors.forename: Marc
authors.initials: M
authors.lastname: Schuckit
authors.forename: Laura J
authors.initials: LJ
authors.lastname: Bierut
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Xuei
authors.forename: Howard J
authors.initials: HJ
authors.lastname: Edenberg
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000201:enzymology / Q000235:genetics*; D000483:Alleles; D002394:Catechol O-Methyltransferase / Q000235:genetics* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006239:Haplotypes; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012307:Risk Factors; D012907:Smoking / Q000235:genetics* / Q000378:metabolism; D044465:White People / Q000235:genetics
chemical_list: D002394:Catechol O-Methyltransferase; D004298:Dopamine