Cystic fibrosis is a fatal lung condition that results from a recessive gene. If one parent is a healthy carrier for the condition while the other is not a carrier, what is the likely outcome for any children they might have?
A) The children will be heterozygous for cystic fibrosis, and all will develop the disease.
B) Fifty percent of their children will develop the disease, and the other fifty percent will be carriers.
C) None of the children will have the disease, and none will be carriers.
D) None of the children will have the disease, but each child has a fifty percent chance of being a carrier.

Question

Quizplus · Accepted Answer

If one parent is a carrier and the other is not, each child has a 50% chance of inheriting the cystic fibrosis gene from the carrier parent. If a child does not inherit the gene, they will not have the disease and will not be a carrier. However, if they do inherit the gene, they will not have the disease, but they will be a carrier. Therefore, none of the children will have the disease, but each child has a 50% chance of being a carrier.

Cystic Fibrosis Is a Fatal Lung Condition That Results from a Recessive