Finally, the geneticists have identified the gene behind the marmalade coloration in domestic cats after 60 years of searching.
Two teams of researchers found any fiery-hued fuzz on our beloved clawed floofs is likely due to missing segment of DNA in a non-protein-coding part of the cat’s genome.
Stanford University geneticist Greg Barsh said it’s been a genetic mystery, a conundrum.
The researcher and his colleagues found cat skin cells from which orange fur sprouts express 13 times as much RNA from a gene called Arhgap36, compared with skin cells from cats with no orange hair.
They were surprised to know it was the sequence preceding it that instead contained a deletion, presumably affecting the rest of the gene’s expression.
The five kilobase deletion was present in every orange cat the researchers examined out of a database of 188 cats that included 145 orange, 6 calico/tortoishell, and 37 nonorange cats.
One finding didn’t come as a surprise. The mutated gene, as long predicted, is located on the cat’s X chromosome. It explained why the orange colour appears so differently between the sexes. Most orange cats are male, while most female cats with some orange fur end up with patchworks of different colours.
