Genetics & Inheritance MCAT Practice Question
A molecular geneticist discovers that a particular human disease follows X-linked dominant inheritance. An affected heterozygous female (X^A X^a) has children with an unaffected male (X^a Y). She is concerned about the risk to her offspring. What percentage of her children are expected to be affected, assuming the condition is not lethal in utero?
Answer choices
- A25% of all children
- B50% of daughters only
- C50% of all children; 100% of daughters and 0% of sonsCorrect answer
- D75% of all children
- E100% of sons only
- FHemizygous males spared from X-linked dominant disorders unlike heterozygous females
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