Molecular Biology/Genetics USMLE Step 1 Practice Question
A 12-year-old male has a particular genetic disease. His mother is a carrier of the mutated gene, but his father is not clinically affected and is not a carrier. The patient has 4 siblings: a sister and a brother who are not clinically affected and are not carriers; a sister who is a carrier but is not clinically affected; and a brother who is clinically affected. This inheritance pattern is most consistent with which of the following diseases?
Answer choices
- ATay-Sachs disease
- BPhenylketonuria
- CCystic fibrosis
- DAlpha1-antitrypsin deficiency
- EDuchenne muscular dystrophyCorrect answer
- FHemophilia A
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