# Technical question



## bluemilk (Oct 3, 2005)

Do Calicos come in both genders?


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## raecarrow (Oct 27, 2009)

> The answer is in genetics. Coat color in cats is a sex-linked trait, a physical characteristic (coat color) related to gender. Female animals have two X chromosomes (XX), males have one X chromosome and one Y chromosome (XY). The genetic coding for displaying black or orange color is found on the X chromosome. The coding for white is a completely separate gene.
> 
> Since females have two X chromosomes, they are able to "display" two colors (orange and black, or variations thereof) and white; creating the 3-color calico mix. Since males have only one X chromosome, they can only be orange OR black. It is more complicated than simply having the color genes -- it is a complex process of dominant and non-dominate genes interacting on the X chromosomes, but that is the basis for coat color in calico cats. For those of you interested in the detailed coat color genetics
> 
> Can a calico cat ever be male? Yes, in rare instances. In this situation, the cat has two X chromosomes and one Y chromosome (XXY). Cats with this chromosomal configuration are usually sterile (not able to breed). This is similar to a condition in humans called Klinefelter's syndrome, or XXY Syndrome.


http://vetmedicine.about.com/od/catbreed1/f/FAQ_calicocats.htm

Fun fact, most male calicos are sterile


> XXY calico cats will be sterile, although there are a few non-sterile males which can only be explained through an even rarer genetic anomaly called a mosaic.
> 
> A mosaic forms when a cat - or other creature - has cells from more than one different cell line in its body. A mosaic cat would have started out as an XXY cell, but after it began to divide, the cat would end up with some normal cells as well. This might also be a cause of male calicos.
> 
> ...


http://www.best-cat-art.com/calico-cats.html


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