Exposure to severe stress early in life increases the risk of alcohol and drug addiction. Some adults who were sexually abused as children – and therefore at high risk for alcohol problems – carry gene variants that shield them from heavy drinking and its negative effects. This is according to researchers at Washington University School of Medicine in St. Louis.
The researchers, from Washington University’s Midwest Alcoholism Research Center, believe the finding could help develop new therapies for alcohol dependence by offering suggestions for targeted treatments. These treatments would be based on genetic traits and a history of exposure to severe stressors. Scientists believe that about half the risk for alcoholism is encoded in a person’s DNA. The remainder comes from environmental factors, like the age of the first drink and exposure to extreme stress. Other research has suggested that when the environmental risk factors happen during key periods of brain development, the genes and environment working together can increase the likelihood a person will develop a dependency on alcohol. Child sexual abuse is an environmental stressor that can interact with genes to significantly increase the risk for an addiction to alcohol.
In the January issue of Addiction Biology, the Washington University researchers said that people with a specific pattern of genetic markers appear to be protected against problems with alcohol, even if they were sexually abused as children. People that were protected have a set of genetic variations called the H2 haplotype. It is similar to a blood type – a normally occurring pattern of gene variants that are connected. When scientists find a few genetic markers, they can successfully predict what other genetic variations will occur within a specific region of DNA.
"We looked at how genes and environment interact," said Elliot C. Nelson, M.D., the lead author of the study. "Our analysis included both sexual abuse and information about the DNA region that carries the H2 haplotype. People who carry that genetic pattern were protected against the risks for alcohol consumption and alcohol dependence typically associated with sexual abuse."
If you or someone you love is struggling with alcohol or drug addiction, know that there is hope.
