What is addiction?
Scientists think that some people are more likely to become addicted than others, because of the influence of their genes. Several different genes could be involved – affecting mood, how much alcohol can be tolerated, and the severity of withdrawal symptoms. If scientists can identify these genes, it may help them to develop new drugs to treat recovering alcoholics.
Are genes involved in addiction?
The brain chemical dopamine seems to be associated with so-called 'pleasure-seeking behaviour'. Scientists have found variant genes in some alcoholics and heroin addicts that may affect the dopamine levels in their brains. These variants may predispose some people to addictive behaviour, but it does not mean that these people are destined to become alcoholics or heroin addicts – they still have control over what they do.
What influences addiction?
Genes are far from the whole story when attempting to explain addiction – circumstances are important, too. For example, a large number of US soldiers became addicted to heroin and cocaine during their service in Vietnam. However, on their return to normal home circumstances, their recovery rate was much higher than other groups of drug addicts, showing that environment and the ready availability of drugs influence addiction rates.