Domesticated cats have been associated with humans for at least 9,500 years. They are currently the most popular pets globally, with approximately 34% of households owning over 88 million cats in the US alone. Thanks to their close association with humans, cats are now found almost everywhere in the world.
The domestic cat was derived from one of the 37 wild species of the Felidae family, and only recently has research brought to light its likely ancestor. Ancient literature is filled with accounts of domesticated cats, and the deification of cats in Egyptian culture has led to the conclusion that cats were domesticated in Egypt. But two studies (Driscoll et al., 2007 and Lipinski et al., 2008) revealed that all house cats were probably descendants of as few as five self-domesticating African Wildcats (Felis silvestris lybica) dating from around 8,000 BC in the Near East and the highest diversity of cats is in the same region. The earliest direct evidence of cat domestication is a kitten that was buried alongside a human 9,500 years ago in Cyprus.
At present approximately 50 recognized cat breeds exist, many of which are moderately inbred. Cat breeds are classified by a variety of criteria, with some, such as the Japanese bobtail, deriving from a single mutation.
The cat has proven to be an important model organism for biomedical research. It is used in understanding mammalian development, cancer research, but especially in infectious disease research. Numerous examples are found in the fields of neuroscience, behavioral biology, reproductive physiology and endocrinology, where the cat has aided human disease research.
The discovery of the feline leukemia virus (FeLV) in the 1960s led scientists to realize that viruses can cause cancer. The high level of similarity among the metabolisms of mammals allows many of these feline diseases to be diagnosed using genetic tests that were originally developed for use in humans. Cats are the only animals other than humans who naturally become sick from immune deficiency viruses. People get HIV, which causes AIDS, while the feline immunodeficiency virus, or FIV, causes a similar disease in cats.
The domesticated cat and its closest wild ancestor are both diploid organisms that possess 38 chromosomes and roughly 20,000 genes. About 250 heritable genetic disorders that are found in humans have been identified in cats, many of which are similar to human inborn errors of metabolism.
Sequencing and genetic mapping has unexpectedly revealed extensive, syntenic conservation between feline and human genomes, in several cases spanning entire chromosomes. The human genome proved more valuable for researchers at The Genome Institute to assist with the construction of the cat assembly than the more closely related dog genome.
It is anticipated that access to The Genome Institute's cat genome sequence will further the understanding of our knowledge gained from their use as models of human disease, as well as assist veterinary research aimed toward better domestic cat health.
-Excerpts taken from Wikipedia