Genetics & Inheritance MCAT Practice Question
A 28-year-old woman and her 30-year-old husband, both of whom are asymptomatic, have a family history of cystic fibrosis. Genetic testing confirms both are heterozygous carriers of the CFTR gene mutation. They plan to have four children. What is the probability that exactly one of their four children will be affected with cystic fibrosis?
Answer choices
- A0.0625
- B0.105
- C0.211Correct answer
- D0.25
- E0.375
- F0.50
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