Inheritance of coat colour

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Inheritance of Coat Colourin Rabbits

BackgroundCoat colour in rabbits is governed by four different

alleles.Each allele is responsible for producing a different coatcolour: dark grey, Chinchilla, Himalayan, and white.

Eachrabbit has only two alleles. Study the relationship

amongthe alleles in the table and then complete the lab.

You Try It1. List all the possible genotypes for a(a) dark grey rabbit(b) Chinchilla rabbit(c) Himalayan rabbit(d) white rabbit

Answer:1. (a) CC, Cch (d) cc Ccch Cc (b) cchcch, cchch, cchc (c) chch, chc

2. Predict the phenotype of a rabbit with the followinggenotypes. Explain your answers.(a) chcch (b) Cch

Answer:2. (a) chinchilla because cch is dominant to ch

(b) dark grey because C is dominant to all other alleles

3. Would it be possible to obtain white rabbits if one parent is white and the other is Chinchilla? Explain.

Answer:3. Yes, only if the chinchilla rabbit is heterozygous with the white allele.cchc X cc could produce a white bunny

5. A Chinchilla rabbit is mated with a Himalayan. Some of the offspring are white. What are the parents’ genotypes?

5. Both parents are heterozygous for the genotype with a white allele. This is the onlyway to get white offspring.

cchc X chc could produce cc = white bunnies.

4. Would it be possible to obtain Chinchilla rabbits if one parent is Himalayan and the other is white? Explain.

4. No, the only possibilities would be Himalayan or white. chch or chc = Himalayan no cch allele present.