The Mutation Behind Calico and Orange Cats

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Purrrfect Mutant

We finally know how cats are orange. Researchers identified the feline alternative to MC1R receptors responsible for most mammalian pigmentation.

• Cat-orange is caused by a mutation of the Arhgap36 gene

• Increases orange and suppresses dark pigments

• Located on the X chromosome = gendered patterns

Females with the mutation often exhibit calico-like patterns, where males are usually a solid color. Further research could uncover more color-defining mutations in cats and other animals. Meow that’s science!

Meowrange

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