A family with only one affected parent and a child with a dominant disease would like to know what the probability is that one of their unaffected children might be a carrier. What do you tell them?

Question

Quizplus · Accepted Answer

In the case of a dominant disease, if a child is unaffected, it means they have not inherited the dominant allele responsible for the disease from the affected parent. Therefore, they cannot be a carrier of a dominant disease allele because being a carrier implies having one copy of the allele without showing symptoms, which is not possible with dominant diseases.

A Family with Only One Affected Parent and a Child