title: Between- and within-family association test of the dopamine receptor D2 TaqIA polymorphism and alcohol abuse and dependence in a general population sample of adults.
abstract: OBJECTIVE
  Dopaminergic dysfunction has been hypothesized to play an important role in the etiology of alcohol-use disorders. A restriction fragment length polymorphism (RFLP) in the 3' untranslated region (3'UTR) of the DRD2 gene affects gene expression and has been implicated as a risk factor for alcohol dependence. This polymorphism (TaqIA) has been reported as positively associated with alcohol-use disorders in case-control samples, but these results have not been replicated in family-based association studies. The mixed results of association between the DRD2 TaqIA polymorphism and alcohol-use disorders may be the result of differences in sample size, phenotype definition, heterogeneity of the samples, and genetic admixture.
  
  
  METHODS
  We conducted tests of association in a sample of 838 adults participating in the National Youth Survey Family Study (NYSFS). We examined whether the DRD2 TaqIA polymorphism was associated with a symptom-count measure of alcohol abuse and dependence derived from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, and the Craving Withdrawal Model.
  
  
  RESULTS
  Tests of association were nonsignificant across each classification system examined. Power calculations suggested that these results were despite the ability to detect an effect size of 1%.
  
  
  CONCLUSIONS
  This study supports other family-based association tests that have reported no association between the DRD2 TaqIA polymorphism and alcohol abuse and dependence.
authors: Institute for Behavioral Genetics, University of Colorado at Boulder, Boulder, CO 80309-0447, USA. brett.haberstick@colorado.edu
authors: Brett C
authors: BC
authors: Haberstick
authors: David
authors: D
authors: Timberlake
authors: Andrew
authors: A
authors: Smolen
authors: Joseph T
authors: JT
authors: Sakai
authors: Christian J
authors: CJ
authors: Hopfer
authors: Robin P
authors: RP
authors: Corley
authors: Susan E
authors: SE
authors: Young
authors: Michael C
authors: MC
authors: Stallings
authors: David
authors: D
authors: Huizinga
authors: Scott
authors: S
authors: Menard
authors: Christy
authors: C
authors: Hartman
authors: Jennifer
authors: J
authors: Grotpeter
authors: John K
authors: JK
authors: Hewitt
mesh_terms: D020413:3' Untranslated Regions / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000437:Alcoholism / Q000453:epidemiology / Q000235:genetics*; D000483:Alleles; D002648:Child; D003430:Cross-Sectional Studies; D015252:Deoxyribonucleases, Type II Site-Specific / Q000235:genetics*; D005260:Female; D015870:Gene Expression / Q000502:physiology; D005828:Genetics, Population; D005838:Genotype; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008957:Models, Genetic; D012150:Polymorphism, Restriction Fragment Length; D011446:Prospective Studies; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D014481:United States
chemical_list: D020413:3' Untranslated Regions; D017448:Receptors, Dopamine D2; D015252:Deoxyribonucleases, Type II Site-Specific; C027046:TCGA-specific type II deoxyribonucleases