Research centers across the United States have compiled a list of thousands of genes associated with alcohol consumption in mice that may have important implications for the understanding and treatment of human drinking problems.
Some 3,800 mouse genes whose activity “significantly and consistently changed between all models of high or low amounts of alcohol consumption” have been identified in the multi-centre effort.
“A prime goal of this research would be a test for a panel of genes that could indicate an inborn vulnerability to alcoholism,” said researcher Susan E. Bergeson, assistant professor of neurobiology at the University of Texas at Austin.
“This could also be important in knowing how one goes about treating it,” she said. “If someone is an alcoholic, it may be helpful to know the genetic makeup of that person. Treatment could ultimately be geared toward the genetic mechanism of that form of alcoholism.”
The studies used three lines of mice bred for high and low amounts of alcohol drinking, five inbred strains known to differ in alcohol intake and a hybrid strain with the highest alcohol intake of any known mouse.
One particularly significant finding was identification of 20 genes on chromosome 9 that are associated with high alcohol intake. Similar genes have been found on the same chromosome in humans, Bergeson said.
The discoveries were made possible by a program sponsored by the U.S. National Institute on Alcohol Abuse and Alcoholism that has allowed researchers across the country to pool their findings, she said. “We are all collaborating with one another. Most of the studies in this paper have not been published before,” she added.
Research on the genetics of alcoholism in humans is at an early stage, with much work still to be done in animals. The first steps already are being taken.
There are a variety of ways to test the role of individual genes, she said. Mice can be bred to lack a specific gene, or the performance of a gene can be lowered or raised to see how it affects alcohol consumption.
The role of specific genes will remain unclear until those experiments are done, Bergeson said. “Many of these genes have not even been characterized yet,” she said. “It’s hard to generate hypotheses at this stage.”
Research in humans will come next, after the role of specific genes is defined. “We don’t expect to find the same mutation in humans, but we hope to identify a pathway involved in the genes that mediates drinking in humans,” Bergeson said.
Source: Susan E. Bergeson, Ph.D, assistant professor, neurobiology, University of Texas at Austin; April 17-21, 2006 Proceedings of the National Academy of Sciences