MZ Twin Concordance Values Are Less Than 100 Percent in Both

question 27

Multiple Choice

MZ twin concordance values are less than 100 percent in both bipolar disorder and schizophrenia. This suggests that these disorders are ______________.

• A) strictly polygenic
• B) multifactorial
• C) X-linked
• D) genetically dominant
• E) not genetically based

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Definitions:

Spotted

Marked with small, roundish patches of color, a term often used in the context of animals, plants, or symptoms of certain diseases.

CFTR Gene

A gene that codes for a protein involved in the transport of chloride ions across cell membranes, mutations of which are known to cause cystic fibrosis.

Mutated

Refers to having undergone changes in the genetic material, leading to a variation from the original.