St. Louis ? Researchers at Washington University and five other centers have identified a gene that is associated with alcoholism in some families.

The scientists, including Danielle M. Dick and Allison Goate of Washington University, are part of a 15-year research project known as the Collaborative Study on the Genetics of Alcoholism. A report published today in the journal Alcoholism: Clinical and Experimental Research, shows that one version of the gene GABRG3 predisposes people to alcoholism. It is the first study to link the gene to dependence on alcohol.

Earlier studies of twins indicated that at least one-third of the susceptibility to alcoholism is due to genetic factors, said William True of St. Louis University. True conducted some of the twin studies.

The new study takes previous genetic research a step further, and will direct other researchers to take a look at how this particular gene reacts to alcohol and how it influences the propensity to alcoholism, True said.

The researchers don’t yet know how changes in the gene, GABRG3 on chromosome 15, increase the risk of alcoholism, Dick said. She said she expected that one version of the gene may interact with other genes to determine whether a person is likely to become alcoholic when they drink.