8. Working on a genetics experiment with Drosophila, you can count the F2 generation of the dihybrid cross between a female fly who has wildtype eyes and vestigial wings and a male who has white eyes but normal wings. An F1 female is then crossed to a true breeding male who has white eyes and vestigial wings. You obtain the following count for the F2 generation (4.0 pts): 64 wildtype (red eyes, normal wings)
896 wildtype eyes, vestigial 932 white eyes,
wildtype wings 75 white eyes, vestigial
a) Calculate the recombination frequency between eye color and wing traits.
11. A dog breeder has noticed some of his male dogs have begun to show a genetic defect, keratitis, in which the cornea of their eyes are easily inflamed, resulting in poor eye sight. The genes controlling this trait are unknown but it is assumed to be a sex-linked gene that it is also recessive. Dogs also have a gene, B, that controls coat color, where black is dominant, B, and yellow is recessive, b. Suppose that the breeder mates a male dog who is normal (XY) and black (heterozygous), with a female dog that is a carrier of keratitis (XXR) and yellow. (5pts)
a)Summarize the possible phenotypes of the offspring (include sex).
b)What are the chances of producing a dog with keratitis?
8. Working on a genetics experiment with Drosophila, you can count the F2 generation of the dihybrid cross between a female fly who has wildtype eyes and vestigial wings and a male who has white eyes but normal wings. An F1 female is then crossed to a true breeding male who has white eyes and vestigial wings. You obtain the following count for the F2 generation (4.0 pts): 64 wildtype (red eyes, normal wings)
896 wildtype eyes, vestigial 932 white eyes,
wildtype wings 75 white eyes, vestigial
a) Calculate the recombination frequency between eye color and wing traits.
11. A dog breeder has noticed some of his male dogs have begun to show a genetic defect, keratitis, in which the cornea of their eyes are easily inflamed, resulting in poor eye sight. The genes controlling this trait are unknown but it is assumed to be a sex-linked gene that it is also recessive. Dogs also have a gene, B, that controls coat color, where black is dominant, B, and yellow is recessive, b. Suppose that the breeder mates a male dog who is normal (XY) and black (heterozygous), with a female dog that is a carrier of keratitis (XXR) and yellow. (5pts)
a)Summarize the possible phenotypes of the offspring (include sex).
b)What are the chances of producing a dog with keratitis?
