New findings on the genetic influences on alcohol use and dependence

Alcohol dependence is a complex disorder with a well documented highly hereditary nature. This article reviews the recent advances in our understanding of the direct and indirect genetic influences on alcohol use and dependence.

Recent findings can be summarized as follows: (a) twin studies have defined and estimated the risks of general and specific alcohol-related vulnerabilities. (b) Linkage studies have provided largely inconsistent findings, though several chromosomal regions have been implicated. (c) Quantitative trait loci analyses in animals have identified that the Mpdz gene predisposes to alcohol dependence and withdrawal. (d) Examination of family-based samples has identified several genes including GABRA2 and CHRM2 thought to be associated with alcohol dependence.

Despite great advances in understanding of genetic vulnerability in alcohol use disorders, only two gene complexes, ADH and ALDH2, have been identified as having defined effects on alcohol use and liability to dependence in humans. New genes associated with increased risks for the disorder will certainly be added to this list in the near future. Neurobiological analyses of the effects of these genes will surely contribute to further understanding of the cause of alcohol dependence and the interindividual differences in risks.