Question

Huntington disease is inherited as an autosomal dominant disorder with adult onset. Sally has Huntingon disease (She is a heterozygote for this gene). Her partner John does not have Huntington. Suppose Sally and John have 3 children. What is the probability that NONE of their children inherit Huntington Disease?

Answer 1

AUTOSOMAL DOMINANT DISORDER:

A person affected by an autosomal dominant disorder has a 50% chance of passing the mutated gene to each child. the chance that a child will not inherit the mutated gene is also 50%. However, in some cases an autosomal dominant disorders results from new mutation or de novo mutation, that occurs during the formation of egg or sperm cells or early in embroyonic development. in these cases, the childs parents are unaffected, but the chid may pass on the condition to his or her own children.