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Carpal Tunnel
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OP
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A bit of trivia: If you see a three colored cat, called a calico cat, you can be positive
it is female. The third color is made possible by gene on the chromosome that males lack.
I'm pretty ignorant about genetics. Anyone who knows more is invited to correct me.
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Carpal Tunnel
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Carpal Tunnel
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I've been told by cat people (of which I'm not one) that this is only a 99% certainty but..
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Carpal Tunnel
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OP
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Here's a URL about the genetics of calico cats. I didn't see any mention of any way males could be calico. I'm too old and tired to really digest the discussion. http://www.fanciers.com/other-faqs/color-genetics.html
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old hand
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old hand
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We call them tortoiseshell cats here, and it is possible to have a male one. The ods are vanishingly small apparently, so that it is almost impossible. I was always taught that it could never happen, until I saw an item on TV news here featuring a male tortoiseshell cat. I guess that shows how rare such an animal is, if it was considered newsworthy.
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Carpal Tunnel
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Charlie is a mean cat and he's a calico. Maybe his problem is an identity crisis.
Now he is a long-haired calico. Don't know whether the long-hair gene makes a difference.
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Carpal Tunnel
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dr. bill, from your link: (I didn't have to click on anything there..)
Dear Dr. Universe,
Q: Are calico cats female only? If so, why?
A: Calico cats are nearly always female. [EA]
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Joined: Jan 2001
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Carpal Tunnel
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Carpal Tunnel
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Dear tsuwm: In another site,it said females were 99%. That's so high, it is easy to understand
why the impression arose that it was 100%. Not many people look closely at that many cats.
"It is dangerous to assert a negative".
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Pooh-Bah
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Pooh-Bah
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The reason that calico cats are almost always female is due to the inactivation of the X chromosome in different cells. All females have two copies of the X chromosome, one inherited from each parent. During fetal development, there is a period when the cells are dividing and both X chromosomes are active. However, after a certain point, one of the two X chromosomes gets inactivated. But this happens randomly, so by the time you have a fully developed animal, you have scattered populations with copies derived from one of the two X chromosomes. The coloring in the fur is controlled at least in part by genes on the X chromosome, so you have patches of fur of different color, each the result of its active X chromosome.
The inactivated X chromosome can be seen in a cell under the microscope, and is called a Barr body, after the biologist who first described it.
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old hand
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old hand
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If I may stray from the subject of gentics, and divert this thread into words, are these cats known by other names elsewhere? It seems unlikely to me that Zild is the only place in the world to call them tortoiseshell. Any takers?
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