The latest news on the animal genetics front is that we have found the gene that makes orange cats orange.

It’s a deletion mutation (and they all have the same exact mutation, meaning all ginger cats are descended from one ginger cat) of the Arhgap36 gene, which is located on the X chromosomes. In humans, the most common mutation of these gene causes alopecia (hair loss). In cats, this particular mutation causes an excess expression of RNA from Arhgap36 which, by some mechanism we’re not clear on, blocks eumelanin production in the hair, allowing only phaeomelanin.

Which is a long way of saying: Orange.