I've got a important question " Are male smoke calico cat's rare and/or exspensive"? I was told they were adn I have one.

-- Anonymous, November 06, 1999

Answers

If by "calico" you mean a colour combination of black and red or grey and peach, with or without white, then the answer to your question is Yes!

The genes for red and black (colour may be diluted by other gened to grey and peach)are located on the X chromosome. To have both black and red, two X chromosomes are required. Usually, a female cat has two X chromosomes while a male cat has only one X chromosome plus a Y chromosome.

However, occasionally, an error occurs in division and distribution of sex chromosomes in egg or sperm (or very early in the kitten's development)so that a male kitten receives an extra X chromosome from one parent. This male will have XXY sex chromosomes instead of XY. Because the kitten has a Y chromosome, it is male. Because it has two X chromosomes, it is possible for the kitten to have the genes for both red and black coat colours.

An XXY cat would be expected to be healthy but infertile. Although a novelty, an XXY cat would likely not be particularly valuable (because it cannot breed).

-- Anonymous, January 31, 2000