ASSOCIATION OF THE D-2 DOPAMINE-RECEPTOR A1 ALLELE WITH ALCOHOLISM - MEDICAL SEVERITY OF ALCOHOLISM AND TYPE OF CONTROLS

D-2 dopamine receptor (DRD2) A1 allele frequency was determined in alc oholics of varying medical severity from three different inpatient set tings and in various controls. A1 frequency was .15 in 68 alcoholics i n a detoxification unit (group A), .19 in 90 alcoholics in a rehabilit ation unit (group B), and .31 in 43 alcoholics in a gastroenterology u nit (group C). Group C had a higher A1 frequency than group B (p = .04 5) or group A (p = .005) alcoholics. In 46 controls (group D), A1 freq uency was .18. In subsets of these controls, A1 frequency was .14 in 3 9 subjects with a negative family history (FH-) of alcoholism (group E ), .06 in 34 subjects without previous hazardous alcohol consumption ( group F), and .05 in 30 subjects with FH- and without previous hazardo us alcohol consumption (group G). A1 frequency was significantly highe r in group C alcoholics than group F (p = .0002) or group G (p = .0002 ) controls; however, no A1 frequency difference was found among group A alcoholics and any of the control groups. The severity of alcoholism and the type of controls used are important determinants of DRD2 A1 a llele association with alcoholism. (C) 1997 Society of Biological Psyc hiatry.