Is There Any Genetic Explanation for Substance Use Disorders

question 222

Multiple Choice

Is there any genetic explanation for substance use disorders?

• A) No; present studies are inconclusive, but the possibility of a conclusive finding remains.
• B) Yes; although at present, only 10 chromosomes have genes related to substance use disorders, the explanation will probably end up being polygenic.
• C) Maybe; there is one "twin" study that seems to support a genetic explanation.
• D) Maybe; those with a substance use disorder are more likely than those without a disorder to have an abnormal D2 receptor gene.

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Definitions:

Increasing-Cost Industry

An industry where the costs of production increase as the industry expands, often due to factors like limited resources or increased prices for inputs.

Market Demand

The total demand for a product or service within a particular market, summed from all individual demands.

LAC Curve

Long-Run Average Cost curve, a graphical representation showing the minimum average cost of production at different levels of output when input prices and technology remain constant.

Constant-Cost Industry

A constant-cost industry is an industry where the costs of production, including inputs, do not change as the industry's output changes.