Genetics

The domesticated cat and its closest wild ancestor both possess 38 chromosomes, in which over 200 heritable genetic defects have been identified, many homologous to human inborn errors. Specific metabolic defects have been identified underlying many of these feline diseases. There are several genes responsible for the hair color identified. The combination of them gives different phenotypes.

Features like hair length, lack of tail or presence of a very short tail (bobtail cat) are also determined by single alleles and modified by polygenes.

The Cat Genome Project, sponsored by the Laboratory of Genomic Diversity at the U.S. National Cancer Institute Frederick Cancer Research and Development Center in Frederick, Maryland, focuses on the development of the cat as an animal model for human hereditary disease, infectious disease, genome evolution, comparative research initiatives within the family Felidae, and forensic potential.

Source : http://en.wikipedia.org/wiki/Cat#Feral_cats