It is the combination of these colors that can create shades such as chocolate, lilac, fawn and cream, and patterns such as calico, tabby, and tortoiseshell. Their patterns are distinct from other particolored cats, such as tortoiseshell cats, who are bicolored as they have only black and orange fur, tabby cats, who have distinct stripy or swirling patterns in their fur, and tuxedo cats who are black with a white chest.Īll cats’ coats originate from two colors, black and red. More specifically, calico coloring is considered to be ‘tricolor’ because, as you probably guessed, calico cats have patches of three distinct colors: orange, black and white. They are one of the particolored colorings as this means that they consist of two or more colors. This means you could have a Calico American Shorthair, a Calico Persian, or a Calico Siberian. Although many people mistakenly view calico cats as a breed, they are actually a coat colouring. Meet the Calico Catįirst, we need to get our definitions straight. While they do exist, male calicos are extremely rare some researchers even suggest that they only they consist of only 1 in 3000 calico cats! In this blog piece, I am going to investigate this phenomenon and attempt to explain the science behind it.

Take your time, I’ll wait…Can’t think of any? Well, that isn’t all that surprising. And if it’s an all orange cat? Chances are he’s male.Here’s a challenge for you: think back over all the cats you know and try to see if you can remember meeting a male calico cat. So the next time you meet a calico, you may want to ask what her name is. Out of the 1 in 3,000 calicoes that is male, only 1 in 1,000 of those is actually virile.īreeders still tend to shy away from these fertile male calicoes, as there are potential health issues that can arise in their offspring due to the extra chromosome. If you spot a male calico, it’s highly likely that this cat is sterile, or unable to reproduce. This cat is almost always male, despite the extra X-chromosome. Given that a cat needs two X-chromosomes in order to have a calico coat, how can one out of three thousand calico cats be male?Ī male cat can have tri-colored fur if he inherits an extra X-chromosome, making his genetic makeup XXY as opposed to XY.

Since white fur is not dictated by chromosomes, this is why you can see male cats with duo-colored coats, such as a tuxedo cat, but not a calico. White fur is determined with a separate gene and may speckle throughout the coat. These random deactivations create either a tortoise shell pattern or calico pattern for the cat’s fur. It’s important to remember that these deactivations are random and are not the same for each cell.įor example, one cell may shut off the X-chromosome that reads “orange fur,” while another cell may shut off the X-chromosome that reads “black fur.” When a female cat is in fetal development, one of her two X-chromosomes is randomly deactivated, which is known as X-inactivation, for each cell. Since a male cat only has one X-chromosome from his mother, his fur color is dictated by that gene. In cats, the X-chromosome is the decider on a majority of the cat’s fur color. In short, female cats have two X-chromosomes and male cats have one X-chromosome and one Y-chromosome. Just like with humans, female cats have two X-chromosomes, one from the mother and one from the father, while male cats have an X-chromosome (from the mother) and a Y-chromosome (from the father).

Are calico cats always female