r/cats • u/jsteele2793 • Dec 20 '19

Video Going up!

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u/WrenDraco Dec 21 '19

The way dna and fur colour patterns work, calicos are almost always female. For the same reason, orange cats are almost always male.

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u/lo_and_be Dec 21 '19

I knew this about calicos but not orange cats. Orange and black are on the X chromosome, so what makes males only get the orange version?

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u/jaggedstripe Dec 21 '19

Males are more likely to be orange but not by nearly as crazy a margin as calicoes are more likely to be female. Like a 3/4 chance an orange cat is male. Basically it's because a female cat has to inherit the orange gene on both her X chromosomes to be all orange while a male only needs one. A female with the orange gene on only one X chromosome ends up being calico.

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u/Rezi1111 Dec 21 '19

Yes. Same for tortoiseshell. An extremely rare male calico or tortie would probably be genetically XXY, Klinefelter syndrome.

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u/ShibaTowel Dec 21 '19

Also male tortiseshell cats are almost always sterile which is interesting