Cats come in a whole variety of colors and shades, but according to the International Cat Association there are just two that are primary. The color black and the color red.
So when you are looking at a cat, what are you really seeing? It is the combination of those two colors, and white, but we’ll get to that in a moment, that make up all the other colors in the kitty rainbow.
Where color originates
It is all in the genetics. Male kittens get both their color genes from their mother. They may be the same color as mom, one of the colors if she has multi-colored, or a dilute variation. Female kittens will get one gene from each parent and will with be a combination of the parent’s colors or a dilute form. That’s the simpler version. It gets far more complicated than that and more information can be found at Cat Fancier’s Association. (http://cfa.org/breeders/catcolorsgenetics/basicfelinegenetics.aspx)
True colors
There are many recognizable colors; black, blue, lilac, gray, cream, red. These are all created from the red and black primary colors. A little more black in the mix will result in the color closer to the black end of the spectrum, such a blue or lilac. More red color will produce shades like brown and cream.
What about white?
White is actually a masking gene. It actually hides the colors. Interestingly, a cat could actually be genetically a black or red cat, but the white gene has come into play. This also means that while a pregnant cat may be pure white, her kittens could be any color – her color without the masking white gene.
Patterns create a difference
Pattern refers to tabby, shaded, smoked or similar, of with the white masking gene adding to the mix. Look at a Tortie cat or kitten, as an example. Although usually female, they are a mix of red and black, but add the white masking gene, you have a calico.
So whatever color and pattern your cat may be, it has all been determined by their mom, if they are a boy, and mom and dad if they are a girl. Just remember, you never know what that white masking gene may be covering. The cat named “Snowball,” may really be “Midnight.”
Somehow that white gene is also linked to blue eyes and the combo often causes deafness. Not sure it’s fully understood yet.
Calico/tortie genes are X linked. Males need either XXY or Chimera (fusion of two embryos in utero) to express the gene, otherwise it’s masked. And it’s the spare X that leaves 99.9
percent of tortie males sterile. (Chimerism is much rarer as the half percent or whatever that can breed)