Your parents are both heterozygous for the recessive disorder phenylketonuria (PKU). What is the probability that you will have the disorder?
A) 25%
B) 50%
C) 75%
D) 100%
E) 25% if your three siblings are healthy; 75% if your siblings also have the disorder

Question

Quizplus · Accepted Answer

Since both parents are heterozygous for the recessive disorder, the probability of inheriting two recessive alleles (and thus having the disorder) is 25% (1 in 4 chance), following Mendelian inheritance patterns. The health status of siblings does not affect an individual's probability.

Your Parents Are Both Heterozygous for the Recessive Disorder Phenylketonuria