This is an entirely new idea. No one has proposed it before and it is speculative but based on good science. It is known that domestic cats with ginger hair are almost 18 times more likely to develop skin cancer than your typical domestic cat with a different coat colour other than white cats who are even more susceptible to skin cancer.
In the news media today, the journalists are reporting on a study which found the origin of ginger hair in people: an ancient frog that lived 10 million years ago.
Palaeontologists at University College Cork found the earliest evidence of pheomelanin, the pigment that produces ginger colouration, in the ancient specimens.
There are two types of pigment that make coat colour and patterns in domestic cats in combination with a wide range of genes: pheomelanin as mentioned and melanin. The former is yellowish in colour and the latter is very dark brown, almost black.
Pheomelanin is the pigment that makes ginger fur coats for cats. Whereas melanin protects people from harmful UV light which can damage DNA in the skin, pheomelanin achieves the opposite. It is phototoxic, and when exposed to light can amplify the processes involved in sun-induced DNA damage. It also uses up a key antioxidant.
My hypothesis is that the DNA damaging properties of pheomelanin in the hair strands of a cat can lead to DNA damage in the skin cells which is why the ginger tabby and plain ginger cats are greatly predisposed to developing skin cancer.
A theory that no one has proposed before – perhaps. Wrong? Tell me in a comment.
Skin cancer can affect any cat, but it is most commonly seen in white cats, ginger cats, or calico cats with lots of white on their ears. That is the norm because white fur does not shade the skin as well as black fur and UV damage to the skin occurs in white cats on the ear flaps where the fur is very thin and relatively sparse.
Around 2 per cent of humans have ginger hair. Around 80% of ginger cats are males due to the gene that signals pheomelanin being sex linked.
