In conclusion, the rs6265 polymorphism may be a risk factor for methamphetamine dependence in south Asian subjects or for heroin dependence in Chinese subjects.
Our findings suggested that the BDNF genetic polymorphism (rs6265) may have effects on the age of onset of heroin dependence among the Chinese population.
These findings support a role of BDNF rs6265 and rs13306221 polymorphisms in heroin dependence and may guide future studies to identify other genetic risk factors for heroin dependence.