title: Heavy nicotine and alcohol use in alcohol dependence is associated with D2 dopamine receptor (DRD2) polymorphism.
abstract: Cigarette smoking in those who are alcohol dependent is associated with higher morbidity and mortality. The A1 allele of the D2 dopamine receptor (DRD2) gene has been independently associated with alcohol and nicotine dependence. Whether this polymorphism is associated with nicotine dependence in those who are also alcohol dependent has not been investigated. Subjects were 84 (61 males; 23 females) Caucasian DSM IV diagnosed nicotine- and alcohol-dependent subjects sampled from consecutive admissions to a hospital alcohol detoxification ward. Data were obtained through standardised measures of nicotine and alcohol consumption and dependence severity. A1+ allelic (A1/A1 or A1/A2 genotype) compared to A1- allelic (A2/A2 genotype only) patients were characterised by higher levels of alcohol and cigarette consumption. A1+ allelic patients reported greater alcohol dependence severity, but not nicotine dependence severity. When the combined nicotine and alcohol dose was examined, A1+ allelic patients consumed significantly more of these drugs than their A1- allelic counterparts.
authors.affiliation: Department of Psychiatry, The University of Queensland, Princess Alexandra Hospital, Brisbane 4102, Australia. Jason.Connor@uq.edu.au
authors.forename: Jason P
authors.initials: JP
authors.lastname: Connor
authors.forename: Ross McD
authors.initials: RM
authors.lastname: Young
authors.forename: Bruce R
authors.initials: BR
authors.lastname: Lawford
authors.forename: John B
authors.initials: JB
authors.lastname: Saunders
authors.forename: Terry L
authors.initials: TL
authors.lastname: Ritchie
authors.forename: Ernest P
authors.initials: EP
authors.lastname: Noble
mesh_terms: D000328:Adult; D000367:Age Factors; D000428:Alcohol Drinking / Q000009:adverse effects*; D000437:Alcoholism / Q000235:genetics*; D000704:Analysis of Variance; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D017448:Receptors, Dopamine D2 / Q000235:genetics*; D012737:Sex Factors; D012907:Smoking / Q000009:adverse effects*
chemical_list: D017448:Receptors, Dopamine D2