MOCHA COLOUR IN THAI CATS
Mocha is a colour found in cats of Thai descent. The dilution factor hasn’t been genetically identified, but appears to be part of the albino series and has been tentatively given the symbol "cm". In Thailand, this colour is being developed in the Bangkok breed, a natural Thai breed which can have blue, aquamarine or odd eyes.
The first of the mocha cats to be identified is Mai Thong. In January 2015, I received information and photos of a native Thai cat that TIMBA hoped to use in the Suphalak breeding programme. Nolan Betterley lives in Thailand and is working on the breeding project to resurrect some of the rare cats that are described in the ancient cat poem manuscripts. Breeders working on the Suphalak, which is a solid (i.e. no Burmese pointing) chocolate self, have searched all over Thailand to find cats suitable to be used in the breeding program. They found cat, Mai Thong, aged approx 7 months, on the street. Nolan hoped that she was either cinnamon or lilac (these are recessives). DNA was tested at UC Davis and came back as aa BB CC DD (Non-Agouti, Black, No Colourpoints, No Dilution), which should produce a black cat. However Mai Thong is very obviously not black, but has an orangey colour. The gene candidates are a non-extension gene (since Russet Burmese exist) or a different form of dilution.
Below is the albino series in cats, from most dominant to most recessive. DNA testing found that “mocha” is an allele of the “C” locus and is co-dominant with both cb and cs (and can't be shown in strict order of dominance in a list). Temperature-sensitive albinism in cats is caused by tyrosinase (TYR) mutations. For the molecular genetically minded, it is a cytosine deletion in the TYR gene. Cat fanciers refer to it as the "C" locus (a sort of genetic "address"). Mocha is not a separate modifier of C.
The remaining 3 cats that failed the test for the Suphalak breeding programme were also street cats; two were brown and one was tortie. They are now in the USA with two different breeders. The plan was to mate them and test offspring, but this has not happened. Doug Schar has the tortie sister. The owner of the other 2 cats has not allowed access to a male sibling for test-mating. UC Davis found no mutation of the TYR gene for these cats. Unfortunately, no other labs appear interested in following up to see what mutation is present..
In April 2016, Janet Poulsen announced this new Thai colour is being imported into her breeding programme in Minnesota. It is speculated that Mocha is in the albino series (tentative symbol cm). If it is not on the albino series, there will be the possibility of some non-black kittens. Mating a lilac boy (CC bb dd - non-pointed, black, dilute) to the imported mocha girl (cmcm BB DD - mocha, black, non-dilute ) will establish whether the new colour gene is on the albino series and fully recessive to C (non-pointed) by producing solid black kittens. Current color tests indicate that the mocha girl is CC, meaning she should be a black cat. She looks like cinnamon but is not (genetically).
Colour tests indicate that the blue-eyed sable Burmese cats are genetically black. So far, a mating of two cbcm (tests as Ccb because there was no test yet for "mocha" cm) cats produced one cbcb, two cbcm (Ccb) and two cmcm (CC in the test available at the time). The cbcm kittens are lighter in color than the cbcb, but still pointed and within the normal color range for Burmese cats. The cmcm (CC) kittens are significantly lighter and though perhaps a bit darker on the nose, they are lighter around the eyes.
Mocha colour restriction was identified in genetically black Thai cats (now called “Bangkok” breed), hence its name. Its effect on other colours (chocolate, cinnamon, blue, lilac, fawn, red, cream) has not been investigated, but may answer long-standing questions about unusual colours reported in Thai cats.
In addition to the mocha colour there are some Sable (Brown) Burmese cats with blue eyes and a kitten that might be pale blue with blue/odd eyes (ash-staining on solid white has also been suggested, but the colour is very even).
Colourpoint varieties in diagram form. Mocha is shown as equally dominant with Burmese and Siamese colour restriction, and the Bur-Mocha and Sia-Mocha intermediates are shown in their correct places.
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