Influence of brain-derived neurotrophic factor (val66met) genetic polymorphism on the ages of onset for heroin abuse in males.

Previous studies have shown that one of the genetic variants BDNF val66met polymorphism is associated with drug addiction. Age at onset for drugs abuse has also been regularly cited as a factor associated with high genetic predispositions. We conducted an exploratory research to investigate the association of BDNF val66met genetic polymorphism with the ages of onset for heroin abuse in males. Venous blood samples from 96 heroin-dependent persons were analyzed by Real-Time Fluorogenic PCR Assay to determine the genotype of BDNF val66met polymorphism. The effect of BDNF val66met genetic polymorphism on the age of onset for heroin abuse was analyzed in the patients of different genotypes. The observed genotype frequency was 32.29% (val66val; n=31), 45.83% (val66met; n=44), and 21.88% (met66met; n=21), which was similar with the reported results of Asians. The onset age was significantly different among the three genotypic groups, and val66met carriers had earlier onset of heroin abuse than did val66val and met66met carriers. Our findings further illustrate the role of BDNF genetic variants in drug abuse and dependence and this study will help to identify who are at risk of becoming heroin dependence in the future and decide the more appropriate timing that interventions should be taken in the high-risk groups.