The D2 dopamine receptor gene and alcoholism: a genetic effect in the liability for alcoholism.

Three of five recent association studies have demonstrated an increased frequency of the A1 allele of the TaqI Restriction Fragment Length Polymorphism (RFLP) of the DRD2 locus in alcoholics compared to controls. One of three family studies has shown preliminary results in favour of linkage of this locus with alcoholism and heavy drinking. The possible mechanism of a genetic effect of the DRD2 locus in alcoholism remains open to speculation, but many involve personality characteristics such as impulsiveness or spontaneity. The applications of the findings of research in this field offer much potential for the prevention and treatment of alcoholism, but also raise certain ethical issues when applied to screening programmes. Future research will be assisted by the development of new, and more informative, genetic markers which are now available at this locus.