Is your cat black and white? Does it look like he's dressed in formal wear? Well, some people think so, which is why black-and-white cats with particular coat markings are called tuxedo cats. It's a trait expressed in multiple cat breeds as a result of genetics.
Clothes Don't Make The Cat
While quite distinct, black-and-white-colored cats aren't a breed unto themselves. Among the Cat Fanciers' Association's list of 42 pedigreed breeds for championship and and miscellaneous classes, multiple breeds can be tuxedo cats. Broadly speaking, cats have genes for orange or black fur as well as genes for white coloring. In addition to a specific set of these genes, a tuxedo cat has particular markings -- that is, white fur on his feet, chest and belly, and sometimes his face.
Black Fur Genetics
If your cat is male, he has one gene for either orange or black fur. The latter is required for a tuxedo cat. In rare cases, male cats can have two color genes, one for each color, but that won't result in tuxedo coloring. If your cat is female, she has two genes for orange or black fur. Only cats with double genes for black fur are black. Combinations of orange and black fur result in tortoise-shell coloring -- a requisite for calico cats, but not tuxedo cats.
White Fur Genetics
Regardless of sex, cats carry genes for piebalding.Technically speaking, the gene expresses as unpigmented fur, but for the purposes of this discussion it's white. When the piebald gene is dominant, cats have more white fur, usually in strips. When it's an incomplete dominate -- i.e., one dominant gene for piebalding, one recessive gene for solid coloring -- cats have less white fur, usually in spots. A double recessive for solid coloring renders cats solid-colored. Cats with either piebald dominant or incomplete dominate genes can be tuxedos.
Not all black-and-white cats are called tuxedo cats. Even with the requisite color genetics, a cat's coat may come in different patterns. The archetypical tuxedo markings are white paws, a white chest and a white belly, but there are many variations. Tuxedo cats may or may not have white on their faces, too, either connected to the chest or as an island of white. Cats of other coloring can have tuxedo markings. Smoke tuxedo cats have grey-blue coloring, for instance, and tuxedo tabby cats have tabby coloring. Such variations involve other genes. Regardless, the term "tuxedo cat" generally refers to a black-and-white cat with tuxedo markings.
- Portrait of a cute black and white cat. image by Gina Smith from Fotolia.com