This article is from the Spring 2003 AFRMA Rat & Mouse Tales news-magazine.
Colors & Coats
By Nichole Royer
Carol Cunningham, e-mail
QCould you tell me if I bred a Burmese Rex with a mismatched Hooded would I have any Himalayan kittens? The female is Burmese Rex (her father was Himalayan and mother was Burmese). The male is mismatched Hooded (black and white) and his father was an Agouti (blue brown) and his mother was Champagne Hooded. Could you also let me know more about the Burmese rats. My female has the colour of a very dark Siamese and is Rex coated. I don’t know much about the breed.
A Siamese Sable mouse.
AMuch to my surprise there is such a thing as Burmese rats (learn something new every day). They look like Sable Siamese mice, and I suspect the genetics are similar. The N.F.R.S. has a picture on their website www.nfrs.org. They also have dark-eyed Siamese and Himalayan now. They are all unstandardized.
We don’t have these new colors but we do have nice dark Siamese rats with beautiful shading and points. There are also poorer colored Siamese with pale points and little/no shading. Then, of course, there are Himalayan rats who are nearly white with fairly light points and no shading. True Himalayans have one Siamese gene and one Albino gene.
Unless your Hooded has a Siamese ancestor in his background somewhere, you will not get Siamese breeding him to your girl. Siamese is a recessive trait and a rat must inherit a Siamese gene from each parent. Your male would have to carry albino in order to produce Himalayan. In order to be Himalayan, the baby has to inherit a Siamese gene from one parent, and an albino gene from the other. Some Hoodeds do carry albino, so it’s possible. I wouldn’t count on it however.
What you will get will depend on what other genes your Siamese and Hooded carry; however, I would expect a litter of mostly black mis-marked babies. Depending on if the Siamese has white markings (very undesirable in breeding quality Siamese), will determine on how much white you would see in the babies. If your Siamese has no white, you will end up with mostly messy Irish markings. If the Siamese has white (ranging from just tail tip/feet/spot on chest to full Berkshire type markings) you will get everything between Irish and Hooded. If you did produce a Siamese or Himalayan out of this breeding, they would have a lot of white markings. This is a very undesirable.
Rex is an interesting gene because it is dominant. This means a rat only has to inherit the gene from one parent to show a curly coat. In this case, you could expect something like half the resulting babies to be Rex. I hope this helps answer your questions.