Vet 101 & Orlando the Marmalade Cat

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We have a double the fun today. Scroll down for more about my latest obsession: Orlando The Marmalade Cat. If you’ve ever wondered why cats come in nearly a rainbow of colors, our vet Dr. G explains at this week’s Q & A.

This week’s reader Q & A with our vet Dr. G. is about cat colors.

Q: This is a stupid question but I’m curious why kittens can look so different from their mother or father? Is it just genetics to get weird looking markings and why are there are so few male multi-colored cats?

A: First of all, always remember: the only stupid question is the one not asked.

The short answer to your question is that cat coat color is one complicated mish-mash of genetics.

The colors in hair, or pigmentation, are caused by the presence of melanin deposited in the hair shaft. There are two different types of melanin: eumelanin, which gives mostly black pigmentation, and phaeomelanin, which gives mostly red-orange-yellow pigmentation. (The absence of melanin produces white color). The concentration, distribution and mixture of each type of melanin is determined by genetics, which ultimately leads to the final coat color and pattern.

One of the most fascinating aspects of genetics is the “randomized controlled chaos” of the whole process. In addition to the genes that control melanin pigment, cats also have genes that control “ticking patterns” (the “agouti” gene), “tabby patterns” (the “tabby” gene), and “shades” of pigment. Multiple genes that can combine in an infinite number of combinations can result in an infinite number of colors. Now add in the possibility of genetic mutations along the way, and the number of variations increases even more. The main blueprint of genetics is provided by the parents, but the expression and patterns of the genes will vary between individual kittens in the litter. Hence, you can end up with a group of babies that may look nothing like their parents! (Add in the possibility that the queen may have bred with more than one male, and your mind is boggled even further!)

Some hair color genes can be “sex-linked”,meaning they are carried on the X or Y chromosome. (Remember high school biology class?) The gene combinations that produce a calico color, for example, are found on the X chromosomes. Since two X chromosomes are required to produce the calico color, and two X chromosomes are required to produce a female, calicos are almost always female (remember XX produces females, and XY produces males). Of course, when dealing with genetics, there’s always that rare chance that you could end up with a mutation that produces the billion dollar male calico…but you might have better luck playing the lottery.

Some color traits can also be linked together. For example, “white spotting” is considered a genetic mutation that causes a “piebald” pattern of white patches. White markings can range from a single spot on a toe, to a completely white coat. The white spotting factor can also create blue eyes, and is often associated with deafness if the white areas reach the ears.

As if cats weren’t complicated enough, now we have one more reason to find them fascinating. Perhaps one day, cats will be able to change their hair color to suite their moods. Now that would be a cat of a different color!

Editor’s Note: If you have a question for Dr. Richard Goldstein, please email it to [email protected]

I’d like to thank one of our readers for recommending a British series of children’s books dating back to ’30s about a marmalade cat named Orlando. How I missed reading the series in my childhood escapes me, but I’m obsessed now.

I found a Orlando the Marmalade Cat Facebook page which lists all 19 books, gorgeously illustrated and written By Kathleen Hale about the globe-trotting adventures of Orlando, his tabby wife Grace and their three kittens: Blanche, Pansy and Tinkle. A few have been re-printed but most are out of print and the rare ones unavailable at any price or pricey like Orlando and the Magic Carpet Check out these covers I know what I want for my birthday…

Have you read any of the Orlando books?