Lack of association between an RFLP near the D2 dopamine receptor gene and severe alcoholism.

Blum et al (1990) have recently examined a restriction fragment length polymorphism (RFLP) detected by TaqI RFLP to the dopamine D2 receptor gene (DRD2) in deceased alcoholics and nonalcoholics, and reported an association between alcoholism and the A1 allele. Subsequent studies, however, by other investigators have failed to confirm this. We have examined the DRD2 TaqI RFLP in 47 living Caucasian males with severe alcoholism. All alcoholic subjects were thoroughly characterized by a structured interview, and met DSM-III-R criteria for alcohol dependence. Only 9/47 (19%) (1990) of these alcoholics had the AI allele compared to 14/22 (64%) reported by Blum et al. This rate was not significantly different from the rates reported in control populations by Blum et al (1990), CEPH, or Bolos et al (1990), and differed only slightly from those reported by Grandy et al (1990). Alcoholics selected for severe medical complications also displayed a similar rate. Our data do not support an association between alcoholism and the D2 dopamine receptor gene in this population.