Red hair is a recessive trait; non-red hair is dominant. Suppose two people
with NON-RED hair have a RED-haired child. What are the genotypes of each parent (use HH, Hh, or hh)? What was the probability of them having a red-haired child?
What are all the possible genotypes of their children?
The genotype of the parents must be Hh. Since they had a kid with a recessive trait with 2 parents who have the dominant trait, they both must carry the recessive trait. The probability was 1/4 or 25%. They possible genotypes are HH,Hh,hH,hh.
