Genetic problems

BIO103-Fall 2020

Genetics Assignment

Please answer the following genetic problems and show how your worked out your answers.

Both typed and hand-written assignments are accepted.

1. A man who is a carrier of sickle cell anemia, a recessive genetic disorder, marries a woman who is not a carrier. What proportion of their children is expected to have sickle-cell anemia? (use the letter s for sickle cell anemia allele and the letter S for the healthy allele)

2. Hemophilia is an X-linked recessive disease that prevents blood clotting. If a woman who is a carrier for hemophilia marries a man who is not a carrier. What proportion of their sons are expected to have hemophilia? (use Xh to denote hemophilia allele)

3. Color-blindness is an X-linked disease. A woman who has a colorblind mother and a father with normal color vision marries a man with normal vision. This couple has a son. What is the chance that this son is colorblind? (use Xa for colorblindness allele, and X for healthy).

4. If a heterozygote blood type A marries a homozygote blood type B.

What are the possibilities of blood types for their children?

5. If a heterozygous purple flower pea plant is crossed with a homozygous white flower plant, what proportion of the offspring will be white flowered?