By Camille Chatterjee, published on January 1, 1999 - last reviewed on December 13, 2006
Mary Jeanne Kreek, M.D., head of the Laboratory on the Biology of Addictive Diseases at Rockefeller University, and colleagues recruited heroin-addicted and drug-free adults to examine genetic differences in their mu opioid receptors—areas in the brain where drugs like heroin bind to create highs.
One mu receptor gene type, dubbed A118G, was significantly more prevalent in drug-free Hispanic subjects than in Hispanics hooked on heroin. Kreek believes that other ethnic groups may also carry this gene. "It's exciting that we've found something that may protect against opioid addiction."