To try and simplify things, if an X chromosome carrying The white coat color gene is switched off in an area of the cat’s body, black or orange fur will grow there instead. This is known as X chromosome inactivation and occurs in the womb when the kitten is just a tiny ball of cells.Īs it’s a random occurrence it means any one color can be deactivated.

To prevent a potentially dangerous double dose of survival proteins, one of the X chromosomes is switched off. However, proteins vital for survival are also found in this chromosome. The gene responsible for coat coloring is found in the X chromosome. Every female has two X chromosomes and males have one X and one Y chromosome. If you’re interested in knowing what makes a cat develop calico coloring, it’s all down to genetics. When the fabric was introduced into America in the 1780s it was known as having a printed design. Made from unbleached cotton, calico is slightly thicker than muslin. If for any reason you have your heart set on a male calico cat, you’ll probably have a hard time finding one! It’s believed that only 1 in 3,000 calico cats is male! Where did the name “calico cat” originate from?Īpart from the term used to describe a type of cat coat coloring, calico is also a fabric. Sadly though, all male kittens born as calico are infertile. Their vibrant coloring gives a stunningly beautiful appearance, and no two are alike. However, if a cat has a mix of blue, grey, and white it’s known as a “dilute” calico. They’re usually a combination of white, orange, and black. What are calico cats?Ĭalico cats have coats that are made up of three different colors. Plus, the variations in color, and personality of these beautiful cats. In this post you’ll learn all about calico cats, what makes them so special, and why it’s rare to find a male calico cat. Actually, calico isn’t a breed of cat but a type of coat coloring. And if it’s an all orange cat? Chances are he’s male.How rare are calico cats and why are calico cats always female? If you’re looking for the answer to these questions you’ve come to the right place. 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).

Calico cat female