The mushroom gene is a recessive
dilution gene
A dilution gene is any one of a number of genes that act to create a lighter coat color in living creatures. There are many examples of such genes:
General
Diluted coat colors have melanocytes, but vary from darker colors due to the concentration ...
that affects red pigment in horses. It was identified in 2014.
On a
chestnut
The chestnuts are the deciduous trees and shrubs in the genus ''Castanea'', in the beech family Fagaceae. The name also refers to the edible nuts they produce. They are native to temperate regions of the Northern Hemisphere.
Description
...
base coat the horse is born a pale beige with sometimes a greyish or pinkish tint and often keeps that color when it becomes an adult, but some turn darker when an adult.
On a
bay
A bay is a recessed, coastal body of water that directly connects to a larger main body of water, such as an ocean, a lake, or another bay. A large bay is usually called a ''gulf'', ''sea'', ''sound'', or ''bight''. A ''cove'' is a small, ci ...
base the horse is born a yellowish beige with a dark contrast stripe on the back, and as it grows older the horse will resemble a
buckskin.
Prevalence
As of 2019,
the dilution has only been found in
Shetland ponies in the United Kingdom. The effect of mushroom on chestnut is very similar to
silver dapple on black, especially because both silver and mushroom give a coat with no reddish tinge. Several ponies with this colour have been tested for the
extension gene and results showed they were chestnut, thus verifying that it affects the "red" pigment pheomelanin.
In 2019 the gene was mapped to the p.Asp201fs frameshift mutation in ''MFSD12''
on equine chromosome 7. MSDF12 (major facilitator superfamily domain containing protein 12) is found in
melanocyte
Melanocytes are melanin-producing neural-crest, neural crest-derived cell (biology), cells located in the bottom layer (the stratum basale) of the skin's epidermis (skin), epidermis, the middle layer of the eye (the uvea),
the inner ear,
vagina ...
s and known to affect pigmentation in humans and mice.
Genetic testing
Genetic testing, also known as DNA testing, is used to identify changes in DNA sequence or chromosome structure. Genetic testing can also include measuring the results of genetic changes, such as RNA analysis as an output of gene expression, or ...
is available for mushroom.
References
External links
"New" Dilutions
Horse coat colors
{{gene-stub