Thrill-seeking genes found

LOS ANGELES, June 30 (UPI) -- At least 20 percent of Americans may be born risk-takers, much more prone than the rest of the population to parachute from planes, bungee jump or become alcoholics, smokers and drug abusers.

In a study published in the American Journal of Medical Genetics, UCLA researchers said they found two types of mutant genes play a role in causing and maintaining personality traits that lead to compulsive thrill-seeking behaviors.

Lead author Dr. Ernest Noble said 30 percent of the population is born with one of the thrill-seeking genes, and 20 percent with both.

Noble told United Press International: ``We looked at the DRD2 and the DRD4 genes alone, and they were both significantly associated with novelty seeking. But when both genes were found, we found that novelty seeking really increased dramatically.''

The researchers evaluated 119 boys, averaging 12 years of age, who had not yet used alcohol or other drugs. They found a ``significant correlation'' between thrill-seeking behaviors and variants of the two dopamine receptor genes. Behavior ``markers'' included excitability, impulsiveness, extravagance and disorderliness.

Noble said the finding could lead to breakthroughs soon in the treatment of alcoholism, drug abuse, obesity, cigarette addiction, and even new drugs to treat people who are too impulsive. He said medications also could be devised to treat those who know they crave danger the way most eople crave food.

But he cautioned that research should not lead to medications ``to drug society to end risk-taking,'' which can be a positive thing for inventors, entrepreneurs and explorers.