The genetic predisposition to alcohol dependence

Genetic effects from the aldehyde dehydrogenase gene localised on human chr omosome 12 have been shown to have a major effect on the development of alc oholism in Far Eastern populations. This effect is caused by a point mutati on in an exon of the aldehyde dehydrogenase gene which inactivates the enzy me, is dominantly inherited and effectively divides the population into tho se at risk and those at very little risk of developing alcoholism. This met abolically induced aversion to alcohol has not been shown in white European populations but it is likely that the alcohol dehydrogenase genes on chrom osome 4 affect some aspects of alcohol consumption both in the Far East and in European populations and that the dopamine D2 (DRD2) gene also plays a part in a subgroup of individuals. The human genome project and recent gene tic linkage studies have brought us to the threshold of a much deeper under standing of how genetic and environmental factors interact in alcoholism. T he well known clinical observation of comorbidity of alcoholism with anxiet y, depression and antisocial personality will soon be understood in the con text of genetic effects from specific genetic susceptibility loci. This gen etic research will reinvigorate clinical epidemiology by helping to identif y environmental factors much more accurately and will enable both improved treatment and prognosis, Curr Opin Psychiatry 12:269-275. (C) 1999 Lippinco tt Williams & Wilkins.