Cat genetics describes the study of inheritance as it occurs in domestic cats. In feline husbandry, it can predict established traits (phenotypes) of the offspring of particular crosses. Inmedical genetics, cat models are occasionally used to discover the function of homologous human disease genes.
The domesticatedcat and its closest wild ancestor are bothdiploid organisms that possess 38chromosomes[2] and roughly 20,000 genes.[3] About 250 heritablegenetic disorders have been identified in cats, many similar to humaninborn errors.[4] The high level of similarity among themetabolisms of mammals allows many of these feline diseases to be diagnosed usinggenetic tests that were originally developed for use in humans, as well as the use of cats in the study of the human diseases.[5][6]
An example of amutation that is shared among all felines, including the big cats, is a mutantchemosensor in theirtaste buds that prevents them from tasting sweetness, which may explain their indifference to fruits, berries, and other sugary foods.[7] In some breeds of cats,congenital sensorineural deafness is very common, with mostwhite cats (but notalbinos) being affected, particularly if they also have blue eyes.[1] The gene responsible for this defect is theKIT gene, and the disease is studied in the hope that it may shed light on the causes of hereditary deafness in humans.[8] Mutations in this gene also cause white spotting.[9]
Since a large variety of coat patterns exist within the various cat breeds, the cat is a qualified candidate animal to study thecoat genetics of hair growth and coloration.[10] Severalgenes interact to produce cats' hair colors and coat patterns. Different combinations of these genes give differentphenotypes. For example, theenzymetyrosinase is needed to produce the dark pigmentmelanin.Burmese cats have a mutant form that is only active at low temperatures, resulting in the dark color only appearing on the cooler ears, tail, and paws.[11] A completely inactive gene for tyrosinase is found in albino cats, which causes a complete lack of dark pigmentation.[12] Hair length is determined by the gene forfibroblast growth factor 5, with inactive copies of this gene causing long hair.[13]
The Cat Genome Project, sponsored by the Laboratory of Genomic Diversity at the U.S.National Cancer Institute Frederick Cancer Research and Development Center inFrederick, Maryland, aims to help the development of the cat as ananimal model for human hereditary andinfectious diseases, as well as contributing to the understanding of the evolution of mammals.[6] This effort led to the publication in 2007 of an initial draft of the genome of anAbyssinian cat called Cinnamon.[3] The existence of a draft genome has led to the discovery of several cat disease genes,[3] and even allowed the development of catgenetic fingerprinting for use inforensics.[14]
^Nie W, Wang J, O'Brien PC (2002). "The genome phylogeny of domestic cat, red panda and five mustelid species revealed by comparative chromosome painting and G-banding".Chromosome Res.10 (3):209–22.doi:10.1023/A:1015292005631.PMID12067210.S2CID9660694.
^Menotti-Raymond M, David VA, Stephens JC, Lyons LA, O'Brien SJ (1997). "Genetic individualization of domestic cats using feline STR loci for forensic applications".J. Forensic Sci.42 (6):1039–51.doi:10.1520/JFS14258J.PMID9397545.
