Expert: Jessica - 2/14/2010

Question
My cat Trick is half black from his mother and Siamese from his father, when he was born and up to his 6th or 7th week of life he was very "Siamese looking", cream colored with black ears, paws and tails and blue eyes. Than he started getting gray, than the gray just blended into black and since I knew both his parents, I knew he was probably just going to look like his mom! Then I found out that all the others except for one turned black! But I saw the litter one week after they were born, they were all Siamese! What gives? Then I saw cats 101 and learned about the "Bombay", that's my cat!!! The similarities are shocking, but Trick's father is not Burmese (Burmese + Black =Bombay),but Siamese. Are you sure there are no breeding subdivisions for Siamese and Blacks? I am tempted to just say my Trick is a  Bombay! I'll send you a picture to prove it!
Thanks,
Sincerely,
Alex

Answer
Hi Alex.  Many times, nature does come up with some very close replications of existing breeds!  For example, there are hairless cats that were assumed to be caused by the same mutation, but when more closely examined, it was found that the hairlessness was caused by two very unique genes, and they are now classified as two separate breeds - the Sphynx and the Peterbald.  This shows us how very different genomes (heredities) can produce very similar phenomes (appearances).

That said, the Burmese is very strongly linked to the Siamese.  The Siamese is a parent breed of the Burmese and was used in breeding programs to develop the Burmese breed until the 1950's.  Considering the Burmese's strong Siamese background, it isn't too surprising that their offspring with a black domestic shorthair would look similar.  While Bombays today come strictly from Bombay lines (no more Bombays are being created without at least one Bombay parent), it might be safe to say your kitty would be a Bombay type.  

Siamese-mix is probably more accurate, since the babies were pointed when they were young, and Bombays are black (or less commonly, sable, the color they will maintain into adulthood).  The reason the kittens were pointed is because of a partial-albinism gene, which is temperature-sensitive.  This causes a lack of pigment on the warm parts of the body.  Kittens are usually born all white, and then color develops on the coolest parts of the body first (ears, face, tail, then legs).  Even pure Siamese continue to darken as they age, and those that are half Siamese can lose the appearance of color points completely.  

Hope that helps!

Jessica