Question

Imagine that head shape is controlled by a maternal effect gene. The dominant h allele produces a oval-shaped head, while the recessive h allele produces a square-shaped head. Imagine that a woman has an oval-shaped head. Her father has the h h genotype. What proportion of head phenotypes do you expect to see in her children

Answer 1

The woman’s genotype is Hh because her father has the genotype hh. If the woman has children with a person who’s genotype is HH, you see 100% oval heads, you’d have genotype HH and Hh. If the woman has children with a person who is Hh, you expect 75% oval heads and 25% square heads with the genotypes HH, Hh, and hh. If she has children with some who is hh, you’d expect 50% oval, 50%square with genotype Hh and hh. To solve, use punnet squares!