The Munchkin cat is a new breed created by a random mutation that produced a cat with extremely short legs. Munchkins come in any coat length or colour. Surprisingly, they are particularly adept at climbing and jumping despite their short legs. They are usually raised as indoor cats, though they are extremely active, agile and fast runners. Those who have spent time around barns have proven to be extremely good hunters. The mutation only affects the length of the legs.
The breed was begun in 1983 when Sandra Hochenedel found an extremely short-legged black cat living under a trailer in Louisiana. The cat, Blackberry, was pregnant and half of her kittens were born short-legged. One of Blackberry’s kittens, a tomcat named Tolouse, became the father of a breeding program and helped establish the breed in North America.
The Munchkin breed is not recognised by all registering associations and is specifically banned by the Federation Internationale Feline FIFe and other European registries as the mutation is believed to be detrimental to the well being of the cat. It is accepted by The International Cat Association TICA.
The munchkin gene is an autosomal dominant one. Thus far to date, there have been no viable kittens that are homozygous for the munchkin gene that is, kittens with two copies of the munchkin gene, one from each parent, possibly because of gene lethality. Kittens that are heterozygous for the munchkin gene that is, a munchkin gene from one parent and a normal gene from the other will be ‘standard’ munchkins.
Because only heterozygous munchkin cats survive to pass on the gene, all litters with at least one munchkin parent have the possibility of having all munchkin kittens, all normal kittens, or a combination of munchkins and normal kittens. A litter with two munchkin parents may be all munchkin kittens, all normal kittens, all non-viable kittens with two copies of the munchkin gene, or any combination of the three.
At one time it was theorized that this short-legged trait was due to the same locus of genes that cause achondroplasia in humans, however, all attempts to prove this to date, have failed. It is now believed to be the equivalent of hypochondroplasia which is much milder than achondroplasia. Achondroplasia affects more than the long bones of the legs. The munchkin cat is shorter than a standard domestic, but in all other respects, it is identical, genetically and in size and overall appearance.