Roanoke Times Copyright (c) 1995, Landmark Communications, Inc. DATE: WEDNESDAY, December 8, 1993 TAG: 9312080035 SECTION: NATIONAL/INTERNATIONAL PAGE: A-5 EDITION: STATE SOURCE: Orange County Register DATELINE: LENGTH: Medium
Half of 53 cocaine addicts tested had a shortage of dopamine receptors in their brains. Dopamine is a chemical that produces feelings of pleasure, said Ernest P. Noble, director of the Alcohol Research Center at the University of California, Los Angeles.
"They don't get rewards from the usual things in life, but when they use substances that release excess dopamine, they get tremendous feelings of pleasure," Noble said.
While people who do not have the defect can become addicts, Noble said, people with the gene defect increase their chance of addiction when they try an addictive substance. The defect also is found in those who abuse alcohol or tobacco or crave carbohydrates, all of which boost dopamine.
"We've always thought that it's kind of a roll of the dice whether people develop addiction problems," Noble said. "Now we think that, for these people, the dice are loaded against them."
Cocaine addicts with the defect tended to have a parent with an addiction to alcohol or tobacco, suggesting that the defect runs in families, he said.
Researchers found 87 percent of their cocaine addicts with the gene defect had a history of truancy, stealing, drinking or fighting before they tried drugs. They also used the most potent forms of cocaine - smoked or injected as opposed to sniffed or ingested.
Noble said the study, published in the journal Drug and Alcohol Dependence, suggests that people who know that addiction runs in the family should avoid experimenting with drugs. Playing sports is an acceptable dopamine boost, he said.
Memo: shorter version ran in the Metro edition.