why are almost ALL calico cats female? why can't male cats have those three pattern?

Question

just curious because my aunt has a female calico cat. she's 16 years old now.

Answer 1

Calico cats, with their orange, black and white coloration, are almost always female.

The answer has to do with genetics. Every cat has 38 pairs of chromosomes; half of the pairs are from the mother, the other half is from the father. Within every chromosome there are thousands of different genes.

Every female cat receives one X chromosome from her mother and one X chromosome from her father, while a male receives one X chromosome from his mother and one Y chromosome from his father. Within the X chromosome is a gene for coat color.

In calicos, one X has the black gene; the other X has the orange gene. White coat color is associated with a completely separate gene.

At conception, the kitten is a one-celled organism, which divides until there are millions of cells that make up the final kitten. Each time a cell divides, it passes on its genetic material.

Gene Inactivation:

For the sex chromosomes, there is a battle for power. This is especially true for the X chromosome. If two X chromosomes are present, which determines female sex, one X chromosome will become inactivated at some point in fetal development. When this happens, all the cells descended from the activated X chromosome will have the same characteristics, including coat color.

In calicos, if the X-chromosome that is left functioning carries the orange gene, then all the cells descended from it will result in an orange color. The same is true if the functioning X chromosome has the black gene. If both X-chromosomes carry the same color gene, then the calico pattern will not appear.

Since X chromosomes inactivate at various times in each individual cat, color patches vary.

The story is different for male cats. Males have only one X chromosome, and it is never inactivated. Whatever color gene is present on this X chromosome will determine the color of the cat. Males can be calico or tortoiseshell only if they are born with 2 X-chromosomes and a Y (XXY), allowing one X to be inactivated. This genetic defect (XXY) is very rare.

Answer 2

I've always heard that there are a lot more female calico cats than males and a lot more male yellow cats than females. I did have one female yellow cat once, but all the others have been male. I've yet to run across a calico male, but I would think they're there, just rare. Why that is? I really don't know.

Answer 3

I don't get why some people are giving thumbs down to those who know their cat genetics and are giving the right answers. Male tortoiseshells and calicos are very rare because it takes a genetic mutation for a male to be able to have both black-based pigment and red based pigment. ( a calico, of course must have both of those plus white) It's only like 1 in 3000 torties or calicos that are male. Red (orange) cats are more likely to be male than female. but the female ones are not THAT rare. they're like around 25% of red cats. The reason the males are more common is that normal male cats get the O or o gene that says whether they'll have red-based or black based pigment only from his mother. So it's easier for him to be just all red (or just all black) For females, they get that gene determining red or black from BOTH parents. So for them to be red, they must get red from both their mother and father. Females might get red from one parent and black from the other - which makes them tortie (or if they also have white then they may be called calico) This cuts down on the number of females who are just either red or black. (But black is more common in cats, so usually people have seen black female cats and dont start thinking they are super rare. Red is a bit less common. so it's more likely someone might not have known a red female) Even if you find another rare male calico that doesn't mean it will be like your buddy Phil in personality. Their colour really does not control that. Phil will always be special and irreplaceable The fact that you cried for weeks shows you have a lot of love for animals. and were able to have a close bond with a cat. Hopefully you will meet some other wonderful cats in your lifetime. They won't be just like him they will be unique, but they can be great friends. .( and i believe you and Phil will eventually see each other again in the next world.)

Answer 4

because...I'll try to keep it simple.

The black and orange coloration of cats is effected by the random inactivation of an X chromosome during development. In a female there are 2 X chromosomes (XX), and one of the X chromosomes are always inactivated for proper development (you wouldn't want 2 functioning X chromosomes)

The orange coloration lies on an X chromosome as well as the black coloration lies on the X chromosome. In females (XX) you can have one X having black and the other X having orange. However during the random inactivation of one or the other X chromosome in the cells of the body during development you get the black/orange random coloration (depending on which X chromosome was inactivated in a certain area, the black or the orange)...

In males you have an X chromosome and a Y chromosome...that X chromosome can contain either black or orange or whatever color...but since there is not another X, you're not going to have another color (except in cases of Klinefelter syndrome in which case a male genotype has an XXY phenotype)

Random inactivation is also why you can't perfectly clone a calico cat (the markings will always be different due to the random inactivation of one of the X chromosomes)...you can look up the cats "CC" and "Rainbow" if you're interested in that.

Good question!

Answer 5

It's just a genetic trait that is passed down through the female genes. It's not IMPOSSIBLE for a male cat to be calico, it's just extremely rare. The same applies to torties, too.

Gorgeous kitties with the triple coloring!

Answer 6

The colour gene is recessive and needs two copies and they are carried on the X (sex) chromosome so because boys are XY they technically can't have two copies of the colour gene to make tortie (calico) so they're usually carrying an extra chromosome XYX which also makes them infertile. Very rarely there is a tortie (calico) male thought to be a chimera carrying a double lot of the XY male sex genes, shown as XY/XY, this can enable fertility too..

Answer 7

X-chromosome inactivation results in this coloring. A female, which has two X chromosomes, can do fine with just one functioning, but it causes a lot of problems in males since they have 1 X and 1 Y, so males must have an XXY genetic defect in order to survive, where they have 2 X chromosomes instead of one.

Answer 8

The statement that orange cats are always male in inaccurate. The orange color comes from different genes, not the sex determing genes.

The pattern is 75% statistically will be male, 25% will be female. Statistically means the chance the cat will be orange and male, or orange and female. I have seen three female orange littermates.

Answer 9

WOW! I never realized that about Calicos and Torties, but yeah, come to think of it!

That is strange..

Answer 10

male calico's are a very rare breed most male calico's are also unable to make babies