Genetic Linkage In Drug Addiction

Based on data obtained from one of the largest family sets of its kind, Yale School of Medicine scientists have identified a genetic linkage for dependence on drugs such as heroin, morphine and oxycontin.

The lead author, Joel Gelernter, M.D., professor in the Department of Psychiatry, said the scientists recruited a sample of 393 small families, most with at least two individuals with opioid dependence. They then searched genetic signposts throughout the entire genome in an effort to identify markers that, within the same family, would show that individuals who share the illness also share marker alleles, or gene variants.

This information allowed the team to identify where genes influencing opioid dependence are located. Gelernter said the scientists found evidence of gene linkage for opioid dependence. They also found good evidence of linkage in the family groups for the symptom cluster traits characterized by dependence on substances other than opioids, specifically, alcohol, cocaine and tobacco.

"These results provide a first basis to identify genes for opioid dependence from a genome-wide investigation," Gelernter said. "Research in the laboratory now is focused on finding specific genes that modify risk for opioid dependence."

He said that eventhough environment plays a significant role, it is well established that substance dependence risk is also genetically influenced. Understanding the genetic factors that influence opioid dependence risk would represent major progress toward understanding the basic biology of the disorder.

"Once specific genes that increase or decrease risk are known, we will be in a better position to figure out exactly what the environmental factors might be and, perhaps, how they can be modified to protect people who are genetically at risk," Gelernter said.



Posted by: JoAnn    Source