A phenotypically normal woman marries a man with CMT disease,an autosomal dominant disorder.They have a son who has CMT disease.How did the son get it?

Question

Quizplus · Accepted Answer

CMT disease is an autosomal dominant disorder, which means that only one copy of the mutated gene is needed to express the disease. The father must have had at least one dominant allele, which he passed on to his son, resulting in the expression of the disease in the son. The mother may have been phenotypically normal but could have carried a recessive allele for the disease, which would not have been expressed in her but could have been passed on to her son.

A Phenotypically Normal Woman Marries a Man with CMT Disease,an