In cats, genes for black (dominant) and red (recessive) colors are allelic and linked to the X chromosome.

In cats, genes for black (dominant) and red (recessive) colors are allelic and linked to the X chromosome. None of these genes are dominant, and when both genes are combined, a three-color cat is obtained. What offspring can be expected from crossing a tricolor cat with a ginger cat?

Let’s designate the chromosome carrying the gene that causes black hair in cats as XB, and the chromosome with the gene responsible for the development of red hair as Xb. The cat’s tricolor coat will be XBXb, which means that all tricolor cats are females.
A tricolor cat will produce XB and Xb eggs.
A ginger cat will be XbY, the sperm it produces will be Xb and Y.
From the described pair of individuals, the following offspring can be expected:
XBXb – female tortoiseshell kittens 25%;
XBY – black male kittens 25%;
XbY – male red kittens 25%;
XbXb – female ginger kittens 25%.