What Is the Most Direct Evidence for a Genetic Explanation

question 9

Multiple Choice

What is the most direct evidence for a genetic explanation for substance use disorders?

• A) Surveys of adults with alcohol use disorder
• B) Higher rates of alcohol preference demonstrated in breeding studies
• C) The study finding that fraternal twins have a concordance rate of 30 percent for substance use disorder
• D) The study finding that individuals with substance use disorder are more likely to have an abnormal D2 receptor gene