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

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Definitions:

Nitrites

Nitrites are chemical compounds that can be used as food preservatives or can occur naturally, but in high amounts can be harmful.

Urinary Tract Infection

An infection in any part of the urinary system, often caused by bacteria.

Specific Gravity

The ratio of the density of a substance to the density of a reference substance, often water, indicating its relative heaviness.

Alkaline

Having a pH greater than 7, indicating a substance's basicity or lack of acidity.