In cats, an X-linked locus is responsible for fur color. There are two known alleles at this locus. One results in black fur color; the other results in orange fur color. A heterozygote animal has patches of orange and black fur (tortoiseshell). Which of the following explains the patches of color in female heterozygote cats?
A) Incomplete dominance of the black fur color allele
B) Fur color is codominant at the organism level
C) Imprinting at the fur color locus
D) Random X inactivation affects fur color

Question

Quizplus · Accepted Answer

Random X inactivation in female mammals leads to the mosaic expression of X-linked genes, explaining the patches of orange and black fur in heterozygous (tortoiseshell) cats.

In Cats, an X-Linked Locus Is Responsible for Fur Color