Researchers have discovered a pair of genetic mechanisms that could hold the keys to gene therapies for alcoholism and depression.
Scientists at the University of North Carolina, led by Dr. Kirk Wilhelmsen, reported in the journal Alcoholism: Clinical & Experimental Research the discovery of a gene that influences individuals’ responses to alcohol. The variant causes a high sensitivity to alcohol in its carriers. Research has shown that others have a much lower sensitivity to the effects of alcohol, which carries a higher risk for alcoholism (people who get tipsy more easily are, conversely, less likely to develop alcoholism).
The gene encodes an enzyme for alcohol metabolization in the brain, rather than the liver as with other alcohol metabolization enzymes. The gene could be useful in determining the likelihood of developing alcoholism.
"Alcoholism is a very complex disease and there are lots of complicated reasons why people drink," Wilhelmsen cautioned in prepared remarks. "This may be just one of the reasons."
In another study, researchers led by Dr. Michael Kaplitt of the Weill Cornell Medical College in New York City discovered that low levels of a protein could help cause depression. The researchers, who included Nobel Prize-winning brain cell researcher Paul Greengard of New York’s Rockefeller University, looked to cure mice bred for depressive symptoms by installing a gene carrying the protein into reward center of the brain. The study, in the journal Science Translational Medicine, showed that the gene-treated mice lost their listlessness and behaved like regular mice.
depressed people display a deficit of the protein. Combined with an existing technique for gene therapy, the results suggest a new way to treat depression, as well as a new target for drugs, Kaplitt concludes.
"No single thing probably causes any human disease," Kaplitt told USA Today. "But we can say there is evidence here of a role of this protein in depression."
Although the study is likely to have a "major impact," neuroscientist Eric Stone of the New York University School of Medicine was skeptical.
“A very elegant and exciting study, it’s going to have a major impact — but I would question any result pointing toward a simple cause for depression,” Stone told the newspaper, adding that drugs are a safer treatment than gene therapy or shunts. Both Greengard and Kaplitt have financial ties to biomedical companies involved in commercializing treatments involving the protein, according to USA Today.