GENETIC PROBLEMS
A woman, who is normal for color vision, has a father that is colorblind. She marries a man
whose mother is colorblind. What is the genotype of the woman and her husband ? What are the
chances that their sons will be colorblind ? What are the chances that their daughters will be
colorblind ?
A woman with freckles marries a man whose parents do not have freckles. Only one of the
woman’s parents had freckles. Freckles is due to a dominant gene. What is the genotype of the
woman ? What is the genotype of the husband ? What are the chances that their children will
have freckles ?
A woman with polydactyly ( extra fingers and toes ) marries a man who does not have the
condition. Only the woman’s mother has polydactyly. Polydactyly is due to a dominant gene.
What is the genotype of the woman and her husband ? What are the chances that their children
will have the condition ?
Lobster claw ( fusing of the fingers ) is due to a recessive gene. Two normal parents have a son
that has lobster claw and a daughter who is normal. What are the chances that their next child
will have the condition ? What are the chances that their daughter is a carrier ?
Free ear lobes is due to a dominant gene. A woman with free ear lobes marries a man who’s
parents both have attached ear lobes. Only the woman’s father has free ear lobes. What is the
genotype of the woman ? What are the chances that their first child will have free ear lobes ?
What are the chances that their second child will have attached ear lobes ?