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Description
The cream dilution gene is one of several genes that will dilute the coat of a horse. Cream is a simi-dominant gene and has a dosage effect
where a heterozygous (nCr), single dilute cream horse will show a lesser effect
when compared to a homozygous (CrCr), double dilute cream horse. In the simplest case, a bay horse with a single copy of cream
is known as a buckskin, a single dilute black horse is know as a smoky black and a palomino
is a chestnut or sorrel with one copy of the cream gene. Double dilutes such as cremellos, perlinos and
smoky creams are chestnuts, bays and black horses respectively that carry two copies of the Cream Dilution gene.
Cream dilution is caused by a gene mutation (in this
case a SNP) in exon 2 of the MATP gene and subsequently, a genetic test has
been developed that tests for the presence of this mutation. There
are other genes that may have an effect similar to Cream dilution
but will not be detected by this test.
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No
Dilution (nn)
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Single
Dilute (nCr)
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Double
Dilute (CrCr)
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Chestnut or Sorrel
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Palomino
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Cremello
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Bay
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Buckskin
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Perlino
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Black
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Smoky
Black
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Smoky
Cream
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Cream Dilution Testing
Animal Genetics offers DNA testing for the MATP
gene mutation responsible for cream dilution.
Cost
$25.00
US per test.
Sample Collection
Collect sample by pulling (not cutting) 20-30
mane or tail hairs with roots attached. It is important that you
pull the hairs and confirm that the actual root of the hair is being
collected. The root contains the genetic material of your horse
that is needed for DNA testing. Therefore, cut hair do not provide
an adequate sample of your horse. Place the collected hairs of each
horse in a separate zip-lock bag labeling the bags accordingly with
the horses name or identification number. Download and complete
a submission form for each sample and send along with payment to
Animal Genetics for testing.
Results
Results are given using the following symbolic
notation:
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CrCr
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Double dilute. Horse
tested Homozygous for Cream Dilution (Two copies of the Cream
allele). Chestnut is diluted to cremello, bay is diluted to
perlino and black is diluted to smoky cream. These colors can
be further modified by the actions of other genes. |
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nCr
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Dilute. Horse tested
Heterozygous for Cream Dilution (One copy of the Cream allele).
Chestnut is diluted to palomino; bay is diluted to buckskin
and black is diluted to smoky black. These colors can be further
modified by the actions of other genes. |
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nn
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Non-dilute.
Horse tested negative for Cream Dilution. Basic colors are chestnut,
bay, black or brown in the absence of other modifying genes. |
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