Is it true that genetics play a role in an individual's drug or alcohol addiction?

Yes.: An early sign of risk of alcoholism is loss of judgement and inability to stop after a relatively small amount.

Unfortunately, yes: Family history is an iimportant risk for developing drug and alcohol addiction. There is something about the brain that one is given, that makes one more susceptible to taking drugs or alcohol.....And those people who are vulnerable, get something extra, that most others do not get from taking drugs or alcohol, which unfortunately encourages the person to take more and more, leading to problems.