Polymorphisms of the dopamine D4 receptor gene (DRD4 VNTR) and cannabinoid CB1 receptor gene (CNR1) are not strongly related to cue-reactivity after alcohol exposure

Addict Biol. 2007 Jun;12(2):210-20. doi: 10.1111/j.1369-1600.2007.00064.x.

Abstract

Polymorphisms in the D4 dopamine receptor gene (DRD4) and the CB1 cannabinoid receptor gene (CNR1) have been associated with a differential response to alcohol after consumption. The goal of the present study was to investigate whether heavy drinkers with these polymorphisms would respond with enhanced cue-reactivity after alcohol exposure. Eighty-eight male heavy drinkers were genotyped for the DRD4 variable number of tandem repeats (VNTR) [either DRD4 long (L) or short (S)] and the CNR1 rs2023239 polymorphism (either CT/CC or TT). Participants were exposed to water and beer in 3-minute trials. Dependent variables of main interest were subjective craving for alcohol, subjective arousal and salivary reactivity. Overall, no strong evidence was found for stronger cue-reactivity (= outcome difference between beer and water trial) in the DRD4 L and CNR1 C allele groups. The DRD4 VNTR polymorphism tended to moderate salivary reactivity such that DRD4 L participants showed a larger beverage effect than the DRD4 S participants. Unexpectedly, the DRD4 L participants reported, on average, less craving for alcohol and more subjective arousal during cue exposure, compared with the DRD4 S participants. As weekly alcohol consumption increased, the CNR1 C allele group tended to report more craving for alcohol during the alcohol exposure than the T allele group. The DRD4 and CNR1 polymorphisms do not appear to strongly moderate cue-reactivity after alcohol cue exposure, in male heavy drinkers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Alcoholism / genetics*
  • Alcoholism / psychology
  • Alleles
  • Arousal / genetics*
  • Beer
  • Cues*
  • Genotype
  • Humans
  • Male
  • Minisatellite Repeats / genetics*
  • Motivation
  • Polymorphism, Single Nucleotide / genetics*
  • Receptor, Cannabinoid, CB1 / genetics*
  • Receptors, Dopamine D4 / genetics*
  • Salivation / genetics

Substances

  • Receptor, Cannabinoid, CB1
  • Receptors, Dopamine D4