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Pearl is a "New" Dilution
Do not confuse pearl with any other dilution
gene.
It is not a form of champagne, cream, silver or dun.
As far as modern equine color genetics is concerned,
it was COMPLETELY UNKNOWN until this decade...even though it may
have existed in some breed(s) for hundreds of years.
Please do not use champagne or cream terms to
describe pearl,
unless those genes are also present.
The Pearl gene is an incompletely recessive, cream-activated, dilution gene.
It is believed to be an allele of cream;
perhaps
a mutation of it.
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Incompletely recessive means that one
copy of the gene in a horse has minimal expression (is almost
invisible), and two copies (homozygosity) results in full
expression (dilutes the base color once).
-
Cream-activated means that it also reacts with cream: it shows up,
adding another instance of dilution, if there is also a cream gene
present. In this case it manifests as a "double dilution": pearl AND cream.
It has been identified so far in American Paint and Quarter
Horses, Andalusians, Lusitanos, Pasos and Gypsy Horses.
Congratulations to all of the
equine color researchers
and breeders who helped identify, name & rename this amazing, elusive,
"incompletely recessive"
and "cream-activated" gene.
The Road to Pearl
Do you have anything to
add to the history
of the discovery of the Pearl gene ?
It appears that Barlnk Peachs N Cream was
discovered to be a "new dilution" in October 2001, and Majodero
R was discovered to be a "new dilution" in November of 2001.
Others quickly followed in the Paint, Iberian and Paso breeds...
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Discovery of the gene in the Barlink Ranch's Paint
Horses
The gene was first discovered by Carolyn Shepard, President
of the International Champagne Horse
Registry, in the American Paint bred horses (click
here to see a copy of her article from the Champagne Horse Journal). She
originally referred to it as "the Barlink dilution gene", since she discovered
it in those American Paint Horse bloodlines. It looked so much like
Champagne that the ICHR still has the first one she found, Barlnk Peachs N
Cream, registered as their only non-champagne!
See "Peaches" here:
http://www.ichregistry.com/studbook_p1_0001-0050.htm She is #0044.
The Discovery of the Iberian "Pearl" gene
The gene also showed up as what most believed was a "different",
cream-activated, recessive, dilution gene. Barbara Kostelnik, co-founder of
the International Champagne Horse Registry, was looking for Champagne in the
Iberian breeds. Concentrating on the lightest colored Iberians, she found that the
stallion "Q" had a foal, "Majodero", that looked very much like Champagne.
The ICHR president, Carolyn Shepard, insisted on DNA color tests, the breeder
obliged, and it was found that he was something "new".
Soon, Celeste Plitz, Deb Morgan, and others were reporting more cases of "champagne looking"
Iberian horses: Andalusian, Lusitano, and Peruvian Pasos.
Barbara gathered everyone connected to these horses (who was
interested) into an internet list named "newdilutions" and created THIS WEB
SITE. She gathered all of the then-current names for the colors, and
suggested that the actual owners pick one. They decided they liked "pearl",
so that is what the list, and this web site, called it from then on.
Carolyn Shepard came to the conclusion that it must
be located at the same locus as cream, because of the way it
inherited.
Then, the first week of October, 2006, shortly after
Carolyn suggested they look at the cream locus, the physical "Barlink" gene was located and
called "apricot" by the equine color genetics laboratory at U C Davis, which
then shortly developed a
test for it.
http://www.vgl.ucdavis.edu/service/horse/
coatcolor.html#pearldilution
The following week, after Carolyn Shepard sent hairs from
Suzan Sommer's "Pearl cream" Andalusian filly, Guindaleza, to UCDavis,
it was found that the gene we had named "Pearl" was the same gene.
For more exact
dates in this timeline, see THIS PAGE.
Shortly after that, the dilution in the Peruvian Pasos was
also identified as that same gene; and now, U.C. Davis is also calling the
gene "pearl".
It was later also documented in the Gypsy Horse and the American
Quarter Horse.
FINDING A "NEW DILUTION"
If you think you have found a horse is a completely NEW dilution, please first try to eliminate, by DNA testing
and
consultation with online horse color sites/experts, all of the currently KNOWN
and IDENTIFIABLE dilutions.
People who understand horse color genetics can identify most
dilutions even without the DNA tests;
that's how it's been done for years, and how these new colors were first
discovered.
If you wish to have complete documentation/proof of your horse's
color (breeding potential), you should have your horse tested for red/black, agouti, cream,
silver (formerly known as "silver dapple", in
some breeds as "chocolate", and in some countries as "taffy"),
champagne, and pearl; also the pinto or leopard/Appaloosa genes, if
there is reason to believe any of those may be influencing your horse's
appearance. Also, remember that horses' colors USUALLY LOOK
COMPLETELY DIFFERENT WHEN NEWBORN THAN WHEN ADULT.
Simply click on your particular area of interest, below or
left, to access the photos and information about it on this site.
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