HeWhoRemains™ Posted April 19, 2023 Posted April 19, 2023 If you've ever cared for a tricolor cat, it's almost certainly a female. Males with three coat colors are very rare: it is estimated that only one in 3,000 tricolor cats is male – although other estimates put this figure at one in a thousand, since it is difficult to verify statistically – , simply because genetics do not allow it. This is the curious reason why the vast majority of tricolor cats are female. THE COLOR IS IN THE GENES The coat of cats can present three basic colors: black, white and orange. The other colors, such as gray or brown, are actually a combination of these. And it is that the color is encoded in two different chromosomes: these contain the genes responsible for pigmentation and the colors that the fur will have depend on their combination. One of these, the gene responsible for producing the white pigment, is encoded on a chromosome possessed by all cats, regardless of sex. Instead, the black and orange pigments are produced by a gene that is only present on the X sex chromosome; and the color that is displayed depends on the allele that a particular individual possesses. Alleles are “alternative” forms of the same gene that produce genetic variations, such as hair color, eye color, or blood group. When a cat, or any other living being, inherits a gene that has several forms, only one of them is expressed. In the case at hand, each allele of said gene activates a different pigment (eumelanin for black and pheomelanin for orange). In females, who have two X chromosomes, there is the possibility that the gene present in each of them manifests itself in the form of different alleles and therefore generates black and orange pigmentation at the same time; Of course, it can also be the case that the genes on both X chromosomes manifest as the same allele and therefore only have one of these pigments. On the other hand, each of the three colors can be manifested or not and, as a consequence, the cats can be one, two or three colors. These can also be combined: for example, a cat that manifests the colors black and white can have gray fur, totally or partially. CAN THE MALES BE TRICOLORED? The case of males is different, since instead of having two XX chromosomes they have one X and one Y. Therefore, there is only one allele responsible for the black or orange color, which can manifest as either of the two and that , as in females, can be combined or not with the gene responsible for the white color and give rise to various possibilities, but always limited to a maximum of two base colours. Or so it should be. The reality is that male tricolor cats do exist, but they are the result of a genetic alteration called Klinefelter syndrome. This mutation only affects males and consists of a duplication of the X chromosome, resulting in an XXY combination or, in rarer cases, even more X chromosomes. As a result, like females, if multiple alleles are manifested in the form of different colors, the male cat may have both black and orange fur; and if the white pigment is also manifested, it will be tricolor. This possibility is very rare: it is difficult to give an exact number, but it is estimated that only one male cat in 1,000 or 3,000 has a tricolor coat, and that even fewer - approximately one in 10,000 - are fertile, since the most common consequence of Klinefelter syndrome is infertility. The reason for this mutation is usually inbreeding, which is why it is more frequent in isolated po[CENSORED]tions and in cats from selective breeding. On the other hand, this characteristic is not hereditary, so if it happens that a tricolor male has offspring, these will not have a higher probability of also being tricolor males. https://www.nationalgeographic.com.es/mundo-animal/casi-todos-los-gatos-tricolor-son-hembras-y-este-es-el-motivo_19352
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