Kevin has curly hair, but both of his parents have straight hair.What might account for their differing phenotypes?

Question

Quizplus · Accepted Answer

Kevin likely inherited a dominant curly hair gene from one or both of his parents. It is possible that his parents are both carriers of the curly hair gene but do not express it because they also carry a recessive straight hair gene. Kevin inherited the dominant gene from one or both parents, resulting in his curly hair phenotype.

Kevin Has Curly Hair, but Both of His Parents Have