Genetics: Analysis and Principles 4th Edition by Robert Brooker

Exercise 4

Mitotic recombination can occasionally produce a twin spot. Let's suppose an animal species is heterozygous for two genes that govern fur color and length: One gene affects pigmentation, with dark pigmentation ( A ) dominant to albino ( a ); the other gene affects hair length, with long hair ( L ) dominant to short hair ( l ). The two genes are linked on the same chromosome. Let's assume this animal is AaLl ; A is linked to l , and a is linked to L. Draw the chromosomes labeled with these alleles, and explain how mitotic recombination could produce a twin spot with one spot having albino pigmentation and long fur, the other having dark pigmentation and short fur.