After over sixty years of researchgenetics has finally revealed the secret hidden behind the orange hair of cats. Two groups of scholars, working independently, have reached the same conclusion: it all depends on one Small portion missing DNAwhich does not codify proteins but plays a crucial role in regulating the expression of a gene called Arhgap36.
This discovery came by analyzing skin cells From which orange hair grow: in them, the arhgap36 gene is activated 13 times more Compared to cats with different color fur. Curiously, the gene itself does not present mutations in its coding sequences. The difference lies in one deletion of about 5 kilobasis which is immediately before its sequence, and which deeply alters the way the gene is expressed.
The difference between males and females
The interesting stretch? This mutation is found on chromosome xwhich explains the obvious difference between males and females. Male cats, having only one X chromosome, express orange uniformly. The females, with two X, instead present a genetic mosaic: some cells use one version of the gene, others the other.
Hence the characteristic cloaks derive turtles or calicowith orange, black and white patches. In very rare cases, even a female can become completely orange: it only happens when Both copies of the X chromosome They present the mutation.
But what exactly does arhgap36 do? The gene, when overexpresso, interferes with those involved in the production of dark pigments, such as Eumelanina, and favors those related to feomelaninresponsible for red and yellow shades. The result is the typical orange mantle.
This discovery not only closes a chapter long decades, but opens new roads in the study of feline genetics and color variations in mammals. And no: however the orange fame have a little careless, No scientific evidence It supports a relationship between the color of the hair and intelligence. In short, behind a simple pumpkin color hides one hides Sophisticated chromosomal dance All to be admired.
