A man and woman undergo genetic testing before conceiving a child. They discover that they are both carriers for Tay-Sachs disease. What are the chances that their offspring will be a carrier for Tay-Sachs disease as well?
A)100%
B)75%
C)50%
D)25%
E)0%

Question

Quizplus · Accepted Answer

When two carriers for a recessive genetic disorder (such as Tay-Sachs disease) have a child, within each pregnancy there is a 25% chance that the child will inherit two copies of the mutated gene (one from each parent), resulting in the child having Tay-Sachs disease; a 50% chance that the child will inherit one mutated gene from one parent and one normal gene from the other parent, making the child a carrier like the parents; and a 25% chance that the child will inherit two normal genes and will not be a carrier or have the disease.

A Man and Woman Undergo Genetic Testing Before Conceiving a Child