Munchkin (cat)
Encyclopedia
The Munchkin is a cat breed created by a naturally occurring genetic mutation
Mutation
In molecular biology and genetics, mutations are changes in a genomic sequence: the DNA sequence of a cell's genome or the DNA or RNA sequence of a virus. They can be defined as sudden and spontaneous changes in the cell. Mutations are caused by radiation, viruses, transposons and mutagenic...

 that results in cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...

s with abnormally short legs. However, the shortness of their legs does not seem to interfere with their running and leaping abilities. The gene responsible has been compared to the one that give Welsh Corgi
Welsh Corgi
The Welsh corgi is a small type of herding dog that originated in Wales. Two distinct breeds are recognized: the Pembroke Welsh corgi and the Cardigan Welsh corgi, with the Pembroke being the more common..-Description:...

s, Basset Hound
Basset Hound
The Basset Hound is a short-legged breed of dog of the hound family. They are scent hounds, bred to hunt rabbits and hare by scent. Their sense of smell for tracking is second only to that of the Bloodhound....

s and Dachshund
Dachshund
The dachshund is a short-legged, long-bodied dog breed belonging to the hound family. The standard size dachshund was bred to scent, chase, and flush out badgers and other burrow-dwelling animals, while the miniature dachshund was developed to hunt smaller prey such as rabbits...

s their short stature; however, Munchkins do not suffer from the many spinal problems that are typically associated with those canine breeds as cats' spines are physically different from dogs'. The spine of a Munchkin cat is usually indistinguishable from that of other cats.

History

Throughout history and around the globe there have been sightings of short-legged cats from Russia to Germany to Great Britain. A breeding population existed in Europe around the middle of twentieth century but the lines died out during and after the Second World War.

The breed was first documented in the United States in 1964 by Ellen Kasten in the town of Westbury, New York. However, the cat was not bred and therefore was not rediscovered until 1983 when a music teacher in Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...

 found two pregnant cats. Half of the kittens of one litter were short-legged, and It is from this line that today's Munchkin breed is descended.

The Munchkin was first introduced to the general public in 1991 via a national network televised cat show held by The International Cat Association (TICA) in Madison Square Garden. Critics predicted that the breed would develop back, hip and leg problems similar to those that plague some Dachshunds. Studies were conducted by Dr Solveig Pflueger (Chief of the genetics committee for TICA) who determined that the Munchkins were physically sound. Amidst much controversy, TICA accepted the Munchkin into its New Breed development program in September 1994. One veteran show judge—who had Munchkin supporters threatening to burn her house—resigned in protest, calling the breed an affront to breeders with ethics. The Munchkin achieved TICA Championship status in May 2003.

Behavioral Characteristics

The Munchkin is generally described as a sweet-natured, playful, people-oriented, outgoing and intelligent cat which responds well to being handled. As pets they are very playful and outgoing; they don't let their shorter legs hinder them from doing things that other cats do.

Physical Characteristics

The Munchkin is a small to medium sized cat with a moderate "semi-foreign" body type. A male Munchkin typically weighs between 3–4 kg (6-9 lbs) and is usually larger than a female Munchkin, which typically weighs between 1,8-3,6 kg (4-8 lbs). The short legs of the Munchkin may be slightly bowed, although excessive bowing is a disqualification in the show ring. Cow-hocked
Cow-hocked
Cow-hocked is the condition in a livestock animal where the back leg joints of the animal are set incorrectly. This term is used to describe when the back 'knee' on an animal is set inward, resulting in a splayed look in the back legs. This can result in the uneven wearing of hooves, which can end...

 legs are also penalized. The hind legs can be slightly longer than the front. According to the Animal Planet
Animal Planet
Animal Planet is an American cable tv specialty channel that launched on October 1, 1996. It is distributed by Discovery Communications. A high-definition simulcast of the channel launched on September 1, 2007.-History:...

 show Cats 101
Cats 101
- Plot :Cats 101 features different cat breeds per episode, which feature many experts, ranging from veterinarians to animal trainers, telling facts, origins, and looks of the breeds. Cat owners of a specific breed also speak of life-changing events that revolve around their cats. It is shown on...

, there are three types of legs on Munchkins: standard, super-short, and rug hugger.

The body of the Munchkin cat is medium sized with a level spine with a slight rise from the shoulder to the rump.

For TICA shows, they are separated by fur length into two groups: Munchkin and Munchkin Longhair. The short-haired variety has a medium-plush coat while the Long-haired has a semi-long silky coat. The Munchkin comes in all colors and patterns. This variety stems from the outcross program, which allows the use of any domestic cat that does not already belong to a recognized breed. Similarity to other breeds is grounds for disqualification.

Health

For the most part Munchkins are a healthy and hearty cat that in general suffer from the same common health problems as other cats but lordosis
Lordosis
Lordosis is a medical term used to describe an inward curvature of a portion of the lumbar and cervical vertebral column. Two segments of the vertebral column, namely cervical and lumbar, are normally lordotic, that is, they are set in a curve that has its convexity anteriorly and concavity...

 and pectus excavatum
Pectus excavatum
Pectus excavatum is the most common congenital deformity of the anterior wall of the chest, in which several ribs and the sternum grow abnormally. This produces a caved-in or sunken appearance of the chest...

 have been documented conditions seen in a few Munchkin cats. These are rare medical conditions seen in other cat breeds too and are not specific to the Munchkin breed.

Dr. Solveig Pflueger, chairperson of TICA's genetics committee and advisor to the Board of Directors conducted studies on the Munchkin cats to determine the over all genetic health of the breed. Based on the research she discovered them to be "happy healthy cats" and that they should have a future as a Championship breed. In 1995 several Breeders had their oldest Munchkins X-rayed and examined for signs of joint or bone problems and no problems were found.

Advocates and critics

The Munchkin cat is the result of a genetic mutation and some people believe that they should not be continued to be bred but others see little difference in a short legged cat breed and the short legged dog breeds such as the Dachshund, Bassett hound and Corgi.

There is controversy among breeders of pedigree cats as to what genetic mutations are abnormal and potentially disadvantageous to the cat. The Australian Capital Territory (a territory of Australia) government consider the munchkin breed to be "malformed animals" and the deliberate breeding of them "unacceptable" because of the "genetic health problems associated with such breeding". Owners and Breeders of munchkins declare them to be "a sound breed" that is "ideal" for small homes and not particularly susceptible to health problems.

Small litter
Litter (animal)
A litter is the offspring at one birth of animals from the same mother and usually from one set of parents. The word is most often used for the offspring of mammals, but can be used for any animal that gives birth to multiple young. In comparison, a group of eggs and the offspring that hatch from...

 sizes when two munchkin cats are crossed indicate that embryo
Embryo
An embryo is a multicellular diploid eukaryote in its earliest stage of development, from the time of first cell division until birth, hatching, or germination...

s which are homozygous for the munchkin gene are non-viable.

Several cat registries
Cat registry
A cat registry is an organisation that registers cats for exhibition and breeding purposes. A cat registry stores the pedigrees of cats, prefixes or affixes of catteries, studbooks , breed descriptions and the standards of points for those breeds; lists of judges qualified to judge at shows run...

 do not recognize the Munchkin: Fédération Internationale Féline
Fédération Internationale Féline
The Fédération Internationale Féline is a federation of cat registries. There are currently thirty-nine member organizations in thirty-seven countries. Membership spans Europe, South America, and Asia....

, which refuses to recognise what they consider a breed based on a "genetic disease", achondroplasia
Achondroplasia
Achondroplasia dwarfism occurs as a sporadic mutation in approximately 85% of cases or may be inherited in an autosomal dominant genetic disorder that is a common cause of dwarfism...

. The Governing Council of the Cat Fancy
Governing Council of the Cat Fancy
The Governing Council of the Cat Fancy is a cat registry, established in 1910 and the largest organisation that registers pedigree cats in the United Kingdom. It was formed from a small number of cat clubs which were registering cats at the time when the modern cat fancy was in its first stages....

 likewise refuses to recognise the breed, considering this breed and others like it to be "unacceptable" because they are based on an "abnormal structure or development". The breed is also not recognized by the Cat Fanciers' Association
Cat Fanciers' Association
The Cat Fanciers' Association was established in the United States in 1906 and is the world's largest registry of pedigreed cats and the predominant pedigreed cat registering association in North America...

.

Apart from TICA, registries that recognize the breed includes The American Association of Cat Enthusiasts, UK's United Feline Organization, the Southern Africa Cat Council, the Waratah National Cat Alliance in Australia, and Catz Incorporated in New Zealand.

Biology

Although the genetic mutation causing the short-legged trait in munchkin cats is often referred to as achondroplasia, it has not yet been proven that the trait is due to a gene at the same locus
Locus (genetics)
In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map...

 as causing achondroplasia in humans. Furthermore, while achondroplasia is typically associated with an enlarged head as well as short legs, a combination of features not seen in munchkin cats, the condition has sometimes been referred to as hypochondroplasia
Hypochondroplasia
Hypochondroplasia is a developmental disorder caused by an autosomal dominant genetic defect in the fibroblast growth factor receptor 3 gene that results in a disproportionately short stature, micromelia, and a head that appears large when compared with the underdeveloped portions of the body...

 instead.

Genetics

The munchkin gene is an autosomal dominant
Heredity
Heredity is the passing of traits to offspring . This is the process by which an offspring cell or organism acquires or becomes predisposed to the characteristics of its parent cell or organism. Through heredity, variations exhibited by individuals can accumulate and cause some species to evolve...

 one. Homozygous embryos for the munchkin gene are not viable due to gene lethality
Gene lethality
Gene lethality occurs when two individuals of the same phenotype mate and a 2:1 phenotypic ratio exists in the offspring . Usually the homozygous dominant individuals will have been aborted before birth....

. Only kittens that are heterozygous for the munchkin gene develop into viable short legged munchkin kittens. Because only heterozygous munchkin cats are able to pass on the gene, all litters with at least one munchkin parent have the possibility of containing kittens with the phenotypes: short-legged or normal-legged (referred to as non-standard munchkin), with the genotypes of Mm or mm, where M is the trait for short legs and m is the trait for long legs. A litter with two munchkin parents, Mm x Mm, have the chance of producing these offspring: 25% MM- a nonviable kitten, 50% Mm-short-legged, 25% mm- normal.

Punnett square
Punnett square
The Punnett square is a diagram that is used to predict an outcome of a particular cross or breeding experiment. It is named after Reginald C. Punnett, who devised the approach, and is used by biologists to determine the probability of an offspring's having a particular genotype...

s, in which the M represents the dominant munchkin gene and the m represents the recessive normal gene, may be used to illustrate the chances of a particular mating resulting in a short-legged cat.

Kittens bearing two copies of the munchkin gene (MM) will not survive. Kittens bearing one munchkin gene and one normal gene (Mm) will be short-legged munchkins. Kittens bearing two normal genes (mm) will be normal. Mm munchkin kittens will be able to pass on the munchkin gene to their own offspring. Normal mm kittens will not, as they do not have a copy of the munchkin gene.
EWLINE
Mating two standard munchkins:
M m
M MM Mm
m Mm mm
this mating, there is a 25% chance it will not survive, a 25% chance it will be normal, and a 50% chance it will be short-legged.

this mating, there is a 0% chance it will be non-viable (unless it has a different, unrelated condition), a 50% chance it will be normal, and a 50% chance it will be a munchkin. EWLINE
M m
m Mm mm
m Mm mm

Recognized crossbreeds

The Munchkin has been crossed with the curly coated LaPerm
LaPerm
The LaPerm is a recognized breed of cat. A LaPerm's fur is curly , with the tightest curls being on the belly, throat and base of the ears. LaPerms come in many colors and patterns. LaPerms generally have a very affectionate personality....

 to create the Skookum
Skookum (cat)
Skookum is the name of a breed of cat. It is a small affectionate cat, very similar to a related breed called the Munchkin, but with curls similar to its other parent breed, the LaPerm. Its head is a broad modified wedge shape with rounded contours and medium large walnut shaped eyes. The head...

, the hairless Sphynx
Sphynx (cat)
The Sphynx is a rare breed of cat known for its lack of a coat.The contemporary breed of Sphynx started in 1966, in Roncesvalles, Toronto when a hairless kitten named Prune was born. The kitten was mated with its mother , which produced one more naked kitten...

 to create the Minskin
Minskin
The Minskin is a breed of cat derived from crossing the Munchkin with the Sphynx.-External links:* The International Cat Association....

, with the uber curly coated Selkirk Rex
Selkirk Rex
The Selkirk Rex is a breed of cat with highly curled hair, including the whiskers . It is distinct from all other Rex breeds. Unlike the Devon Rex and Cornish Rex, the hair is of normal length and not partly missing, and there are longhair and shorthair varieties...

 to produce the Lambkin, the Persian to create the Napolean and crossed with the Bengal
Bengal (cat)
The Bengal is a relatively new hybrid breed of cat, formed by the cross of a domestic feline and an Asian Leopard Cat .Bengal cats have "wild-looking" markings, such as large spots, rosettes, and a light/white belly, and a body structure reminiscent of the Asian Leopard Cat...

 to create the Genetta.

See also

  • Cat body type genetic mutations
    Cat body type genetic mutations
    Cats, like all living organisms, occasionally have mutations that affect their body type. Sometimes, these cat body-type mutations are striking enough that humans select for and perpetuate them...

  • Scottish Fold
    Scottish Fold
    The Scottish Fold is a breed of cat with a natural dominant-gene mutation that makes its ear cartilage contain a fold, causing the ears to bend forward and down towards the front of their head, which gives the cat what is often described as an "owl-like" appearanceOriginally called lop-eared or...

    , a variety of cat with a gene causing osteochondrodysplasia
    Osteochondrodysplasia
    Osteochondrodysplasia is a general term for a disorder of the development of bone and cartilage .-Achondroplasia:Achondroplasia is a type of autosomal dominant genetic disorder that is a common cause ofdwarfism...

     rather than achondroplasia
    Achondroplasia
    Achondroplasia dwarfism occurs as a sporadic mutation in approximately 85% of cases or may be inherited in an autosomal dominant genetic disorder that is a common cause of dwarfism...

    .

External links

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