Cystic fibrosis is inherited as an autosomal recessive condition. A normal couple has one daughter affected with the disease. They are now planning to have another child. What is the chance of her sibling being affected by the disease?
High-Yield Explanation
Siblings have one in four chance of being affected in Autosomal recessive diseases. Ref: Robbin's Basic Pathology, 7th Edition, Page 215.