Monday, October 31, 2011

Myth or Reality: Is it true that all tricolor and tortie cats are female?


Yes, the explanation lies in the genes. The coat color of cats is inherited from the parents of the animal and the genes of colors (black, white and yellow) are present on chromosome X. In reproduction, the female goes to the baby like an X chromosome and the male can send an X, giving rise to a female (XX) or a Y, forming a male (XY). Each cat, therefore, has a pair of genes related to color (one gene from the mother and one from the father) and these genes can be either dominant or recessive.
For a female to have three colors she must possess an X chromosome with the gene and the other yellow X with the dominant white gene.
Males usually have hair unicolor or bicolor. In the latter case, the possible combinations are orange and white or black and white.
A tricolor male is the result of a genetic abnormality, with a probability of occurring less than 1% and it would also have two X chromosomes (one with the yellow gene and the other with white), and the Y chromosome, which makes the male. This results in a chromosomal aberration. When this rarity happens, the tricolor cat (XXY) is sterile.

Helena Rios, DVM