Is a Person Predisposed to Drug Addiction by Genetic Factors Or Environmental Factors?

It has long been known that children raised in families where drug abuse and addiction are present are statistically more likely to experience those same problems in their own lives. What hasn’t been clear is whether this propensity was the result of exposure to the addictive behaviors, or some genetic command. Recent discoveries brought the answers nearer.

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Is a Person Predisposed to Drug Addiction by Genetic Factors Or Environmental Factors?