My life is a cat life

genetics guide

Color restriction (tyrosinase, TYR): Mutations on this gene will result in temperature-sensitivity in the pigment production, the cats will be lighter on the warm and darker on the cooler areas of their bodies.

dominant allele: C - regular pigment production, full colored cat (wild type)

allele: cb - moderately reduced pigment production: burmese color restriction, sepia cat (variant)

allele: cm - reduced pigment production, bangkok color restriction, mocha cat (variant)

allele: cs - highly reduced pigment production: siamese color restriction, pointed cat (variant)

recessive allele: c - no pigment production, albino cat (variant)

Order of dominance: C > cb = cm = cs > c

For the sake of aesthetics, the only variant allele I depicted is the rarest cm.

further destription in this post

Karpati (?): This unidentified gene makes the extremeties (face, ears, legs, tail) white kinda like a reverse colorpoint cat, and causes a roaning effect: scatters white hairs everywhere on the body.

dominant allele: K - whited extremities, karpati cat (variant)

recessive alleles: k - normal pigmant production, full colored cat (wild type)

further information in this post

Bonus: Temperature sensitivity

I've mentioned previously that colorpoint and karpati kinda looks like each other's inverse.

(This cat has a very good karpati effect, most of them has lot less white on their nose and around their muzzle - most likely it's a quite old one.)

Do you know what connects the body parts that are dark on a pointed and light on a karpati cat?

Well, look at this image:

It's an infrared photo; it shows the heat emission from the cat. (Well, if it's real. But even if this particular illustration is computer-made, the phenomenon it shows is real.) You can see that the legs, the tail, the face and the ears are the coldest areas.

The pigment production in colorpoint and presumably karpati cats is heat-associated: it's efficiancy declines or rises with the temperature.

Before they born, the kittens bath in the even warm of the womb, so first they're even colored: white for a colorpoint and almost full black (or the respective color) for a (hezerozygous) karpati.

An all colorpoint litter and a karpati litter with one(!) non-karpati. Look for the white ears!

After a few weeks, their colors are already much more developped:

(Same litters as above)

Oké, actually we don't really know how karpati works. Some heat sensitivity is very likely, but the cats' color changes during their lives definitely don't depend only on the temperature, since these very spectacular kittenhood patterns quickly fade away and then comes back slowly and very differently depending on individual. (Again, this is only true for heterozygotes. Homozygotes don't lose all their whiteness.)

The temperature sensitivity can result in really funny patterns in colorpoint cats: if a cat loses some of its fur for some reason, and later it grows back, it'll be noticeably darker then the surrounding area, because the naked skin means the temperature is lower there.