A calico kitten is a kitten with three separate, well-defined colors in its coat. Calico cats are not a specific breed, so both purebred and mixed-breed kittens can have the calico gene and develop this coat color.
The three-color pattern defines the calico. The colors of a calico cat are usually black, white and red, but some have one or more diluted colors instead, such as grey and cream, in place of the red and black. If the cat has multiple colors but is lacking white, it is considered a tortoiseshell cat.
Calico kittens develop their distinct coat pattern because different patches of fur express different forms of the same gene. In most calico cats, this gene is on the X chromosome, so a cat with two different X chromosomes might have a gene for black or white on one and a gene for orange on the other. In different patches of skin, one of the two X chromosomes is inactive, making that patch the color designated by the other X chromosome. The on-and-off pattern of these chromosomes is randomly set when the kitten is in the womb. It is nearly impossible to breed cats specifically to create a calico cat because the genetic activity of the calico trait is unpredictable.
Most calico cats are female because male cats only inherit one X chromosome. However, male calico cats do sometimes occur if the male cat has a chromosomal abnormality. The most common type of chromosomal abnormality seen in male calicos is the presence of three sex chromosomes. These cats have an XXY genetic profile instead of the normal XY of males or XX of females. According to Cornell University College of Veterinary Medicine, the odds of a male kitten being calico are about 1 in 3,000. Most male calicos are sterile, but some can sire kittens when they grow up.
The behavior of a calico kitten depends more on the specific breed of the kitten and its individual personality than on the kitten's calico coloring. A calico Maine coon is likely to display that breed's fun-loving, intelligent personality, while a calico Persian may be more likely to have a sweet, gentle temperament. Of course, all kittens tend to love exploring and playing while they are young, so your calico kitten probably won't develop distinct breed personality traits until she is older.
Calico cats are beloved the world over. In 2001, the state of Maryland named the calico cat as its state cat. In Tokyo, cat lovers have create an entire cafe dedicated to the calico cat, which is considered lucky in Japan. At the cafe, visitors can have tea or coffee while petting and playing with one of the resident cats that roam the premises.
Bridget Coila specializes in health, nutrition, pregnancy, pet and parenting topics. Her articles have appeared in Oxygen, American Fitness and on various websites. Coila has a Bachelor of Science in cell and molecular biology from the University of Cincinnati and more than 10 years of medical research experience.