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 The Pearl color varieties
and their genetics
It is believed that pearl and cream are alleles at the
same locus.
Thus, this site will use these three abbreviations for the three
possible alleles at the cream locus:
prl (pearl gene), Cr (cream gene)* and cr (neither)
Pearl and "neither" are represented
lower-case
because
they are recessive to cream*.
Cream* is represented with the upper case "Cr"
because it is a(n
incompletely) dominant gene.
(The lighter gray-colored notations in parentheses with "N" in them are
used by some laboratory reports,
and are only included here to help readers interpret those reports.)
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cr cr
= no pearl and no cream gene present
(N/N)
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This horse will have no change in its coat
or skin color due to either
the pearl or cream genes. It may be a solid dark
color,
or it may have variations caused by OTHER color modifying
genes.
-
If bred, it will pass NEITHER a cream* nor a
pearl gene to its foal.
If a foal from this horse has a cream* or a pearl gene, it
has to
have come from the other parent.
-
prl cr = one pearl gene,
no cream gene (Prl/N)
-
This horse will look almost identical the
one above,
except the coat color may be the slightest bit lighter,
almost like a lighter shade of the dark color,
and the dark skin may have pink dots in places.
-
If bred, this horse has a 50% chance of
passing along the pearl gene to each foal.
-
Cr prl = one cream and
one pearl gene [(Cr/N) and (Prl/N)]
-
This horse will look similar to a
double-cream or champagne color when it's born.
This means blue eyes, pink skin, and a distinctly diluted
coat color. As it matures,
the coat will lighten more, to almost a completely
double-cream diluted color.
The skin will develop freckles similar to champagne, but
muted in contrast.
-
If bred, this horse will always pass along
one or the other gene to its foals.
Each foal has a 50% chance of inheriting the cream gene, and
a 50% chance
of inheriting the pearl gene, but NEVER BOTH, and ALWAYS ONE
OR THE OTHER.
-
The foal's appearance will depend upon
which gene the cream pearl has passed on to it,
and what other genes the other parent has passed on to it.
Depending upon what genes it gets from its other parent,
it could be a double-cream, a homozygous pearl,
a single cream or a single pearl.
-
prl prl = two pearl
genes; homozygous for pearl (Prl/Prl)
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This horse will be born with blue eyes and
purplish pink skin,
and a moderately diluted coat color.
As the foal matures, the skin may darken to a deeper
purplish pink,
and will develop freckles much like champagne freckles.
The coat (hair) color may lighten a bit with maturity,
but will not become as light as a double-cream* or a pearl
cream dilute.
-
If bred, this horse will always pass along
one pearl gene. However, as always
with pearl, its presence will scarcely be noticeable unless
the foal also inherits
a pearl gene or a cream gene from its other parent.
-
If two horses with prl,prl (two pearl genes
each, or each homozygous for pearl)
are bred together, the foals will ALWAYS have two pearl
genes (prl, prl).
Examples
cr cr - no cream, no pearl.
These horses will not have diluted coat color, unless they have
other dilution genes such as champagne or dun causing it.
prl cr - one pearl only, no cream
Also called single pearl, pearl, or pearl carrier. Some of
the APHA (Barlink, etc.) horses of this type have the pink dots on
their skin, and some of the Iberians of this type have slightly
lighter coat and eye color than normal. I will endeavor to add
pictures of both, and also pictures of single-pearls with no
discernible dilution, like RD Chica.
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This is RD Chica, the first Iberian pearl-carrier ever
identified. This mare was DNA tested to rule out her being
a smoky black, as she appears, and was found to be "just a
chestnut". Obviously, the slight dilution caused by a
single pearl gene was not enough to overcome her extremely dark
"liver chestnut" base color. Perhaps she would have been
even a little darker without the pearl gene.
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The Peruvian Paso mare in this photo has only one pearl gene. See
also the dam of Heather Batkin's cream pearl filly, farther down on this
page.
Bravio, the second horse determined
to carry a "hidden" pearl gene.
Cr prl - "cream pearl" - one pearl and one cream gene
Depending upon the "base" color of the horse (red or black-based),
this combination produces particular, predictable effect. The skin
and eye color is usually the same (described above) regardless of the
base color.
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On chestnut (red based): the horse will end up looking like a
pale Palomino.
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On bay, brown or black (black-based): the horse will end up
looking like a pale buckskin with tan or brown points instead of
black.
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The first Pearl dilute that was ever discovered by this
webmaster was Majodero R, a SMOKY BLACK PEARL (solid black plus
one cream gene plus one pearl gene.) He was exported from
the USA to Australia, where we believe he still lives.
E_aaCrcr (DNA) IALHA #5987SP, foaled May 30, 2001 out
of RD Chica, a liver chestnut pearl carrier;
sired by
Q, a perlino.
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This Peruvian Paso filly is also a SMOKY BLACK
PEARL. This color is the result of one pearl and one cream
gene on a solid black base. She is believed to be
the only horse of her color in New Zealand. She is the
second example we've seen of how much darker
these colors are in
newborns.
Heather Batkin, her breeder, writes that this filly is:
"...out of my Black/Pearl mare. Born 10th Dec 2009 8pm. She's a
smoky black pearl..." Also note the dark
pearl-carrying mare shown here. |
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Guindaleza R is a PALOMINO PEARL, which is one pearl and one cream gene on a
chestnut base. She's the daughter of Chica (see above) by
Saphiro, a cremello. Owned by Sommer
Ranch.
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prl prl - double, or homozygous pearl
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<= on black: E_ aa prlprl: Avispado, in Spain, is the first horse of this color ever
discovered by this webmaster. He was first presented to her as a
possible champagne, which, sadly, his owner calls him today. He is, however, something even rarer.
Having DNA tested E, aa, prlprl ... he's a solid black based
homozygous (double) pearl.
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<= on bay, with gray added: Ee Aa prlprl Gg : Zorita Surprise, breed unknown so far, imported to Norway
from the Netherlands in utero (unbeknownst to the mare's new
owner!). The dam's color was brown. Sire is unknown
to date. Zorita has had one foal by a homozygous gray
stallion. The foal looks bay with dorsal and leg striping. Zorita's owner at first assumed she was some kind of
champagne, until she was DNA tested (She was nearly even
registered by the ICHR!) DNA testing yielded the results
above. (More photos coming)
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We have received beautiful photos of a stallion in Russia believed
to be homozygous pearl on bay, but until this is verified by parentage,
progeny, or DNA testing, we can't include him on this page.
See him here. |
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