i heard that you cant get male tortoise shell cats, only females - is this true?

Question

if it is true, does anyone know why the colour tortoise shell is only available in female cats?

Answer 1

Coat coloration in cats is complex, and controlled by several genes. One gene involved has two alleles: the Orange allele, O, which is the dominant form, (i.e., XO), and produces orange fur; and the "Black" allele, "o", which is the recessive form, (i.e., Xo), and produces black fur.

For a cat to be a tortoiseshell or calico, it must simultaneously express both of the alleles, O and o, which are two versions of the same gene, located at the same location on the X chromosome. Males normally cannot do this: they can have only one allele, as they have only one X chromosome. Virtually all tortoiseshell or calico cats are females. Occasionally a male is born (the rate is approximately 1 in 3,000 [2]). These may have Klinefelter's syndrome, carrying an extra X chromosome, and will almost always be sterile or they may be a chimera resulting from the fusion of two differently coloured embryos.

Answer 2

As a cat lover myself I always considered the above assertion to be true.
That is until one day, when I visited a cat protection league re-homing centre, and saw a female ginger cat suckling her litter of three (all ginger) kittens.
In order to explain this we need to consider Kitty genetics. All cats have 19 pairs of chromosomes, and like humans, cats have one pair of sex chromosomes. These are the ones that make them male or female and they play an essential role in determining their colour.
In females, both sex chromosomes are X making females XX. Males are XY, the Y making them male.
The gene which makes a cat ginger is located on the X chromosome. The gene for mighty ginger will override all other colours. Since males have only one X, they either are or aren't ginger. Female cats have two X's in each cell. As far as the cells are concerned two X's is one too many, so each cell deactivates one of the X chromosomes in a fairly random fashion. Sometimes the ginger X will be left on producing a bit of orange fur and in some cells the ginger X will be turned off and the genes for black, brown or other colour fur will be produced. And there you have Tortoiseshell Cat. Since males only need to have the orange gene on one chromosome to become ginger, and females have to have it on two, ginger males outnumber females 3 to 1. To show both orange and another colour such as black or brown a cat has to have two different X chromosomes per cell. Therefore tortoiseshell female cats outnumber males by at least 200 to 1, although I suspect actual figures are much higher. When a male tortie does appear, (a result of a mutation producing two X¿s and one Y) he is invariable sterile and may even exhibit feminine behaviour such as nurturing nearby young.

So the answer to your question is that your observation is, AS A RULE OF THUMB, spot on as far as tortoiseshell's are concerned, although female gingers are fairly common.

HOWEVER I have a Beautiful fluffy fat MALE Calico. Best cat I've ever owned. He's like a dog and follows us around everywhere. The vet confirmed he is the 1st he has ever seen in his 22-year career.

Its rare but so is an honest politician!

Answer 3

The calico color is carried in the X gene of cats and requires 2 X chromosomes to create this is why male calicos are extremely rare. It's not true that most do not live that are born male. Male calicos are actually hermaphrodites because their genes instead of being XY are XXY which means they carry female and male genes. Male calicos are always sterile. It is impossible to breed 2 calicos cats.

Answer 4

Tortoise shells are similar to Calico's...Males are rare and when you find them they are usually sterile and cannot reproduce. So there are a few Males running around.

Wikipedi has the technical reason for the coloring.

Answer 5

Yes, to a point.
Both the genes for the black and ginger colours are found on the X chromosone. in a female Tortie, she has patches of black, patches of ginger and patches of white (where both colour genes cancel each other out). A male with two X chromosones is possible, but they usually die at a few days old, if they are born live at all. It is usually due to a random mutation in his genes that means he has too many, i.e. XYX rather than XY, so they are sickly and unlikely to live.

Answer 6

It is true to an extent. My Grandma has a male tri-colored cat, he is retarded. He freaks out once and a while, i mean just acts like he has no sense. He isnt mean, but its so funny. He is a healthy cat too. He has good weight, no alergies, I;ve never seen him sick. Neat cat, really, and he's nice too. She took him to the vet to have him spayed but the doc started lookin around and said, "spaying this cat isnt gonna do any good, its a boy". It happens but not often

Answer 7

I don't think it's true. It's like people say that you can't have a ginger female cat but I've known one and own a ginger female.

Answer 8

male tortoise shells are very rare just like male calico's. its to do with the combination of colors.

Answer 9

yes it's true mostly. They are very rare, male torties, rarer than the all ginger female cat, which are not supposed to happen but do (cos we have one).

Answer 10

I think in extremely rare cases it can be male, but I've also heard that the male ones are born sterile, so they can't reproduce.



http://www.messybeast.com/tricolours.htm