Genetics of responses to drugs of abuse

Genetic differences in drug metabolism, in the number of drug receptors in the brain, and in drug-seeking behavior may contribute to the variability of individual responses to drugs of abuse. Genetic models include inbred strains, mutants, sublines, and selectively bred mice and rats. They have been used to examine acute and chronic effects of narcotics, stimulants, and alcohol as well as drug-seeking behavior, withdrawal syndromes, and the stress-induced release of endogenous opioids. These genetic models should prove helpful in defining individual differences in susceptibility to addiction.