September 19, 2026
Orange girls, tortie boys, and a little cat genetics
I kept hearing that orange cats are always boys, and that a male calico is basically impossible. That did not sit right, so I looked it up.
I found the simple answer is that orange color sits on the X chromosome. Girls have two Xs. Boys have one.
A boy only needs one orange X to be fully orange. That is why most orange cats are boys. A girl needs orange on both Xs to be a fully orange girl. That happens. It is just less common, so orange girls stand out.
Torties and calicos are a mix of orange and not orange. That mix is much easier when there are two Xs, so these cats are almost always girls. Add white and a tortie becomes a calico, like Cali: patches of orange, black, and white.
A tortie or calico boy is rare. He usually has an unusual set of chromosomes, or he grew from two embryo cells that fused together. A lot of those boys cannot father kittens. If you ever meet one, it is a real treat!
If you are peeking at our Jacksonville kitties, look twice at the coats. You might spot an uncommon combo or two; or you might fall for an ordinary color with an extraordinary purr. Both are a good reason to say hello.
Jamie
Cali's Kitty Friends