 Munchkins
are distinguished by shortness of the legs. They are sound and
healthy cats; through many years of genetic testing and breeding
they have proven free of any defect or spinal problems.
The breed is being reestablished in long or short coats and a
variety of patterns and colors. They maintain their kitten
personality for their entire life, making them the perfect choice
for the person who desires a kitten that never grows up.
The
Munchkin cat is a relatively new breed created by a random mutation
that produced a cat with extremely short legs. Munchkins have short
or long coats in a wide variety of colours. Somewhat surprisingly,
because of their short stature munchkins are particularly adept at
climbing and jumping. They are usually raised as indoor cats,
although they are reported to be 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 Fédération Internationale Féline
FIFe and other European registries, but it is accepted by The
International Cat Association (TICA).
Genetics
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.
Punnett squares
Punnett squares, 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
munchkin 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 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 kitten will not, as it does
not have that gene.
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