Wednesday, March 18, 2009
Baby is my resident tortie (aka "tortoiseshell"). What I didn't know when I got her is that torties have a reputation of having an attitude, or "tortitude". A quick internet search found these words that describe torties: aloof, independent, feisty, unpredictable, and mean. Good thing my cat doesn't cruise the internet. Baby is a sweet, huggable, lap kitty, that loves to spend time with her humans. She nestles with Jack and Simon, and sleeps on my legs at night. But her favorite thing to do is cuddle in my husband's arms like a baby with her belly exposed.
Tortoiseshell cats are not a breed, but a color. The "O" gene which is responsible for the ginger color is found on the X chromosome. A male cat is XY, so he will be ginger if he inherits the "O" gene. Since a female cat has XX she can be ginger if she inherits two "O" genes, or tortie if she inherits only one. Therefore, only females can be torties. (It is very rare to find a male tortie. He would be XXY and sterile.) The patches of a calico cat and brindle pattern of a tortie are caused by a process called X-chromosome inactivation. Some skin cells activate the "O" gene on one chromosome, while other skin cells activate the "o", or black gene, leaving the "O" inactivated. I have seen tortie persians, tortie point siamese, tortie longhairs, and of course short hair torties like my Baby.