Orange cats, also called ginger cats, have a reputation as being male, large, very food-motivated, and kind of goofy. Scientists at Kyushu University in Japan and Stanford University, working on a crowdfunded project, have located the gene that causes a cat to be orange. The culprit is a mutation on the ARHGAP36 gene. A missing inhibitor section in that gene causes more activity, and the result is that the cat's melanocytes -cells that control color- are ordered to produce a lighter pigment, meaning orange.
The reason that orange cats are overwhelmingly male is because the ARHGAP36 gene is carried on the X chromosome. Male cats only have one X chromosome, so if a male cat inherits the mutation, it will be orange. Female cats have two X chromosomes, so they must inherit both X chromosomes with the orange mutation to appear orange, as only one such chromosome will likely produce mixed colors, like tortoiseshell or calico. The kicker is that the ARHGAP36 gene also controls other parts of a cat's anatomy, such as the brain and hormone production. The missing inhibitor DNA in a mutated ARHGAP36 gene may explain why orange cats have other similarities that give them the stereotype. Read more about this research at BBC. -via Damn Interesting
(Image credit: Mike Lehmann)