Genetics & Inheritance MCAT Practice Question
A 28-year-old woman with a family history of hemophilia A presents to genetic counseling before planning pregnancy. Her father was diagnosed with hemophilia A at age 5 years. She is phenotypically unaffected but is confirmed to be a carrier of the Factor VIII mutation. Her partner is an unaffected male with no family history of bleeding disorders. Based on this cross, what is the expected genotypic ratio among their daughters?
Answer choices
- A1 X^A X^A : 1 X^A X^aCorrect answer
- BAll X^A X^a (100% carriers)
- C1 X^A X^A : 2 X^A X^a : 1 X^a X^a
- DAll X^A X^A (100% unaffected)
- E3 X^A X^A : 1 X^A X^a
- F2 X^A X^a : 1 X^a X^a
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations ā plus adaptive practice that targets your weak areas ā with a free MedBoardPRO account.