What outcome is likely if both parents are carriers of PKU?
A) One child out of four will develop the disorder.
B) None of the children will develop the disorder.
C) Their daughters are more likely to develop the disorder than their sons.
D) All of their children will develop the disorder.

Question

Quizplus · Accepted Answer

PKU (Phenylketonuria) is an autosomal recessive disorder, meaning that a child must inherit two copies of the defective gene (one from each parent) to develop the disorder. If both parents are carriers, there is a 25% chance (or one in four) that any given child will inherit two copies of the defective gene and thus develop PKU.

What Outcome Is Likely If Both Parents Are Carriers of PKU