![]() So, if you see a calico cat, even at great distance, you can be sure that it’s a female. Therefore, it’s not possible for an XY cat (a male) to have one gene for saying yes orange and a matching gene saying no orange. There’s no space for a matching gene on the Y. In cats, the gene for orange hair colour happens to lie on the X. Hence there isn’t room on the Y for all the genes that fits on the X. The two kinds of sex chromosomes differ greatly in size and shape. Mammals with two X chromosomes are female (XX) those with one X and one Y are male (XY). Sex chromosomes come in two flavours: X and Y. These cats have a Y chromosome but instead of just one X, they have two. In some rare cases, however, a cat is born with a condition called Klinefelter syndrome. Male cats normally have XY chromosomes and therefore only one of the orange or non-orange genes. The chromosome pairs come in a variety of sizes and shapes, but except for the so-called sex chromosomes, the two members of a pair are always the same size and shape as each other. For this reason, tortoiseshell and calico cats are almost always female. In this case, for reasons to be explained later, the result is a mosaic– some hairs orange, some black. brown, the dominant brown gene always wins over the recessive blue, at least in humans.) Sometimes the method of conflict resolution is more complicated.Ĭalico cats arise when the genes controlling orange coat colour disagree: The gene from one parent says yes, the hair should be orange the gene from the other says no, it shouldn’t. ![]() Often a simple choice is made, depending on which gene is dominant and which is recessive. “When the gene from the mother disagrees with the gene from the father, some mechanism must be used for deciding the nature of the offspring. In her research, she discovered that it’s almost genetically impossible for male cats to get three colours. She found that the answer lies in how their chromosomes function. In a book called ‘Cats are not peas’ by Laura Gould, the author deep-dives into the genetic reason for calico coloured cats. However, there are other explanations from more recent times that are based on scientific research.Ĭalico cats are always almost female– the answer to why lays in their DNA. When the offspring of these cats made kittens, the ‘mi-ke’ (three-fur) cat was born, which gave way to what we know today as the calico. In Japanese culture, it is believed the first cats to arrive in Japan were black, followed by white, and at last, orange cats. This is why a female cat can have three colors and therefore a tricolor or calico coat: they have an X chromosome for black, an X chromosome for orange, and white is expressed independently.Calico cat in its natural habitat – staring at people with malice.Ĭalico cat | How do cats become tricoloured? The white color, however, is not linked to sex chromosomes. Females have two X chromosomes, so they can have genes for both black and orange and thus create tortoiseshell patterns. Males only have one X, so a male cat will only be either black or orange. In other words, for these colors to show, the cat must have the X chromosome. The information for black and orange colors are in the X chromosome. Depending on the combination, the cat can be male or female. The mother always gives an X chromosome, and the father can give X or Y. ![]() ![]() Cats, like all mammals, have two sex chromosomes: X and Y. Sex chromosomes are the ones that determine the sex of the cat. Cats have 38 chromosomes: 19 are provided by the mother and 19 from the father. Therefor, the color and pattern of the cat's coat is a feature that is linked to its sex.Ĭhromosomes are structures found in the nucleus of cells that contain all of a living organism's genetic information, that is, its DNA. The color and pattern of a cat's coat depends on the animal's genes more specifically, the information for hair color is coded into the two chromosomes that determine the animal's sex. ![]()
0 Comments
Leave a Reply. |