In cats, the genes that control coat color are located on the X chromosome and show incomplete dominance

In cats, the genes that control coat color are located on the X chromosome and show incomplete dominance. Gene B determines black color, gene b – red color, and heterozygote for this gene has tortoiseshell (tricolor) color. What kittens will be born from a black cat and a ginger cat?

Let’s designate the chromosome containing the gene that causes the development of black hair in cats as XB, and the chromosome with the gene for red hair as Xb. The tortoiseshell (also called tricolor) coat color of cats will be written as – XBXb and are found only in females.

The black cat, according to the introduced designations, will be XBXB, it will produce the same type of XB eggs. The ginger cat will be written XbY and will produce Xb and Y sperm.

Kittens that can be born to the presented pair of parents:

XBXb – female tortoiseshell cats 50%;

XBY – black cats 50%.