| THE PAPILLON INFORMATION SITE
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| PAPILLON COAT COLORS SITE |
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COAT COLOR GENETICS IN
PAPILLONS AND PHALENES
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DISCLAIMERS:
1. The following information on the inheritance of Papillon (dog) coat colors is
based on our knowledge and research and is intended
for casual readers who are interested in learning a little about color genetics. Those
who wish to have a more comprehensive and accurate understanding are encouraged to read
other sources.
2. The photographs used on this website are to demonstrate color only! We do not endorse the quality of the dogs nor their breeders.
3. ALL the photographs used on this website are used with permission.
Please do not copy or use the photographs without obtaining permission.
We are not authorized to give permission to use any of the photographs
unless we have the copyright.
4. Those wishing to reprint this text may do so with our permission which will
be granted so long as proper credit is given.
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INTRODUCTION:
There are about ten different genes that affect coat color in all dogs.
Each of these genes is located on a different chromosome and therefore
the different genes for color are independent of each other. The area on the chromosome
that a gene is located on is called a locus (plural is loci). The ten loci for color are as
follows: A, B, C, D, E, G, K, M, P, and S. Each loci has one gene located on it,
but each gene has at least two variations of itself called alleles.
Typically the alleles follow a hierarchy of dominance. For example,
if a gene has three alleles called "1", "2", and "3",
allele "1" will be dominant to both "2" and "3."
Allele "2" will be dominant to allele "3" but it will be recessive to allele "1."
Finally, allele "3" will be recessive to both allele "1" and "2."
All of the alleles affect color by controlling the distribution and
depth of the two types of pigment.
Distribution refers to the location and pattern of the color on the coat and
depth refers to the shade of the color.
All of the various colors that produce a Papillon's coat color are produced by
only two pigments. They are eumelanin and pheomelanin.
eumelanin which produces black/brown colored hairs and
pheomelanin which varies in color from pale cream to red to dark mahogany.
To avoid rewriting all the different shades produced by the pheomelanin pigment,
it is often said that pheomelanin simply produces red colored hairs.
White hairs are often referred to as colorless hairs because they are produced from a
lack of both eumelanin (black & brown) and pheomelanin (gold) pigment. Also, it is
important to note that in addition to all the alleles that control coat color there are
"plus" and "minus" modifiers that influence the color by controlling the distribution
(location of the color) and depth (shade of color).
The "plus" modifiers act to produce more pigment while "minus" modifiers
restrict pigment. Unfortunately, these modifiers aren’t completely understood.
The key to coat color is in cells called melanocytes which belong to
a larger group of cells called neural crest cells. These cells migrate into the
skin during early development. Some of these cells remain in the skin while others move
into the developing hair bulbs which produce hair. Melanocytes produce granules of
pigment called melanin of which there are two types. As mentioned earlier, eumelanin
produces black/brown color and pheomelanin produces all shades of gold. The second part
to pigment production is controlled by modifier genes. These modifiers affect the
distribution (location), and depth (shade) of color.
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S-Series = WHITE
The S locus has 4 different alleles that determine the distribution
of colored and non-colored (white) areas on the coat. The S-series only determines
where the colored spots will be. The actual color of the colored spots is
determined by other genes.
The four alleles in dominant-to-recessive order are:
S, si, sp, and sw.
These alleles dictate how big and where the colored and white spots will be. In addition
to the four
alleles at the S series, "plus" and "minus" modifiers also affect color and the amount of
white on the coat. "Plus" modifiers produce more color throughout the coat while "minus"
modifiers restrict pigment and allow for more white. Further, the S-Series seems to
be affected by environmental factors that play a role in determining the size and
placement of the white spots. These environmental factors are not predictable and are not
yet completely understood.
SELF-COLOR:
The S allele allows for full pigmentation on the coat. In other words, a dog with a S
allele will be of a solid color and will have virtually no white anywhere on its coat.
However, because of "minus" modifiers, a small amount of white on the toes, chest, belly,
or tail tip can sometimes occur. Due to selective breeding, this allele is not present
in Papillons.
IRISH SPOTTING:
The si allele is responsible
for the Irish spotting which is characterized by white hairs covering the muzzle, chest,
underbelly, tail, and one or more feet. Due to modifiers, the size of the white areas
does range from small white areas to very large areas. However, generally there is more color
than white on the coat. Typically the white spots tend to be symmetrical.
Again, due to selective breeding, this allele seems not to be present in Papillons.
PIEBALD:
The sp or piebald
allele is responsible for producing a coat which is about
50% white and 50% color. Papillons are affected by the
sp allele for piebald. Normally, the white areas are found on the chest, neck,
legs, belly, around the loin area, and the tip of the tail. However, due to modifier genes,
there is a lot of
variation in the amount of white that an individual Papillon can have.
Some Papillons have
more color than white due to the affect of "plus" modifiers while others may have a lot more
white due to "minus" modifiers. There have been a few Papillons who have had so little
white that they appeared to have Irish spotting.
On the other end, there are some Papillons that have had so much white that they appeared
to be extreme piebald (read next section below). Historic photographs do show solid white Papillons
and the FCI does accept solid white Paps. However, it seems that today, the
sw allele for extreme piebald has been virtually bred out of the breed and most
Papillons who have an extreme amount of white, including mismarks, are
homozygous [spsp] for piebald with a lot of "minus" modifiers.
Even though the exact amount of color and white spotting is not very important to breeders,
provided that there is color covering both eyes and ears,
some have refrained ,from breeding Papillons that are extreme at having either
too much color or too much white. Some breeders point out that a mating between
two very white Papillons has a greater chance of
producing mismarked offspring.
EXTREME PIEBALD:
The last allele in this series, and most recessive is the
sw or extreme piebald pattern. In its most extreme form, the
sw allele is responsible for an all white dog. Sometimes, the dog may have
some color spots on its body or head particularly in a light cream color. "Plus" modifiers
allow more color and less white to be present while minus modifiers restrict the presence
of color and allow for more white on the body.
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Locus A = AGOUTI, SABLE, TRICOLOR, and RECESSIVE BLACK
In hierarchical order, the alleles in the
A series are: possibly aw, ay, at, and possibly a.
The A series is responsible for
both allowing eumelanin (dark pigment) to be shown and restricting it to allow gold
hairs to show. The degree of restriction, or lack there of, is determined by the 3-5 alleles
at this series and by modifiers that work in conjunction with these alleles.
AGOUTI:
The first allele in this series is aw for agouti which has not been
definitely established. Wild color or agouti is where all the hairs on the coat are banded.
It is believed by some, that the shaded sable is agouti. The shaded sable will have
colored hairs that are red hairs that have black tips.
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SABLE:
The next allele in hierarchical order is the ay allele for sable.
Sables express both eumelanin (black) and pheomelanin (red) in a sporadic manner. Throughout the coat,
there will be individual black hairs dispersed among the gold areas.
There are two main elements that deal with the color sable. First, is the amount of black
that a Papillon has in its coat and second, is the shade of the pheomelanin (red) hairs.
Amount of black hairs:
The ay allele restricts eumelanin (black pigment)
in the coat and allows gold hairs to develop. There is a variance in the amount of
eumelanin pigment that is restricted because of modifiers.
Normally sables are born with a lot of black hairs at birth.
With age, modifier genes may shut off the production of melanin and turn on pheomelanin production
in certain individual hairs. As a result, a hair that was originally solid black will
begin to grow out gold. Therefore, the individual hair would be gold at the root
and black at the tip. If the production of eumelanin and pheomelanin
continues to switch the Pap will have banded hairs for most if not all of its life and
may be referred to as a shaded sable.
Generally, though, the banded or tipped hairs will be shed and replaced with
solid gold hairs. So, a puppy that was born with a lot of black hairs will grow up to have
less black hairs and more gold hairs. The result is a typical sable Papillon with more or less
black overlay. Some Papillons, particularly those who were born with less black hairs, will
shed so many of their black hairs that they will have virtually no black hairs as adults.
These Paps are referred to as clear sable.
Some sables do re-grow some black hairs later in life particularly on the ears and at the
base of the tail. This is most evident on clear sables. There is some evidence suggesting
that sables with the genotype [ayat] (read below on at allele)
may have more black hairs than the sables with the genotype [ayay].
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Shade of gold hairs:
The shades of gold on sable Papillons include pale cream, orange, bright red,
dark mahogany, and every shade in-between.
There are two reasons why the gold hairs range in so many shades.
The first is that modifier genes influence the depth of the gold pigment.
These depth modifiers seem to account for the orange to mahogany shades and for the fact
that an individual sable Papillon can have several different shades of gold on its coat.
Typically, lighter gold hairs are found on the face, belly, and under the tail, while darker
gold shades are found on the ear fringe, and along the back.
The second reason why the gold hairs range in so many shades is due to a separate gene
that is found on the C locus (read below to learn how the C
locus affects the shade of the gold hairs). The cch allele from the C locus dilutes the gold
hairs into an extremely pale yellow/cream shade. These sable Papillons are referred to as lemon.
These Papillons are registered as "sable" with most dog registries, but we feel that because it is a
separate gene that causes this dilution to the coat color, it would be acceptable
to register them as "lemon sable".
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TRICOLOR:
The fourth allele, at, is responsible for the tricolor. A tricolor
has solid black body spots and gold markings which are more commonly referred to as "tan"
points. The tan points are located over the eyes, a little on each cheek, some in the ears,
and under the tail. The tan points range from shades of pale cream to deep red. This
wide range in color is often the result of modifier genes which affect the tan points just
like they affect the shades of sables. The extremely pale yellow/cream tan points are
most likely caused by the cch allele from the C locus (read below).
There are also minimal tricolors
and hound tricolors. Minimal tricolors are tricolors where some or all the tan points are missing. Often the
minimal tricolor will have more pronounced tan markings at birth which will gradually
become smaller. This is most likely due to modifiers that promote eumelanin pigment or
due to a mask (read the E locus section below) which hides some of the tan points.
Because a mask is always black, it is often difficult to discern if a tricolor has a
mask or not. However, the hairs where there is a mask
will often be a darker black which can best be seen in sunlight. Hound tricolors, are Papillons that have tan heads and white and black on their bodies. Usually
the hound tricolor will look a lot like a classic tricolor when it is born, but over time,
the tan points on its face will spread and cover the most of the face. This is
probably due to modifiers that inhibit eumelanin pigment. A different variation of the hound tricolor is where the
face retains the classic tricolor’s tan points, but gold or tan hairs are produced at the
back of the head. Another variation
that can affect any tricolor is when tan "extensions" spread to the leg area.
Interestingly, because Papillons have white legs, the white "hides" the tan markings
that would otherwise be there.
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RECESSIVE BLACK:
The fifth and most recessive allele, a, in the A series is responsible for recessive
black. This allele has not been scientifically established but many breeders believe
that it does exist in certain breeds like Shelties and German Shepherds. Recessive black
produces the same effects
that the As allele (discussed above) produces except the a allele is recessive
to all the other alleles on the A series.
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Locus B=BROWN:
The next series of discussion is the B series which affects coat color and leather color.
The B allele allows for normal black pigment which
results in black hairs and a black, nose, eye rims, lips, and pads.
The homozygous recessive [bb] allele combination dilutes black hairs into brown and the nose, eye rims, lips, and pads
will also be brown. It is also responsible for producing green or amber colored eyes instead
of the typical brown eyes. The variation in shades of brown from very dark to
extremely light appears to be due to genetic factors other than changes in the b gene itself
(Little 42). However, any shade of brown is commonly referred to as liver or chocolate in Papillons.
There is even a liver tricolor which has the [atat] genotype on the A locus and [bb]
on the B locus. Even though a double dose of the b allele dilutes black hairs, it does not
have any effect on the gold hairs. A red liver Papillon has [ee] alleles on the E locus
(read below) and [bb] on the B locus. If you remember from reading the Color Page, a
red Pap has no black hairs so it consequently cannot have any brown hairs.
It will have brown leather, though.
Because the Papillon standard calls for black pigmentation on the eye rims, nose, and lips,
breeders try to avoid the liver color. Consequently the brown color has become quite rare in
Papillons.
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Locus C = FULL PHEOMELANIN, CHINCHILLA, ALBINO:
On locus C there are three and possibly four alleles. In dominant to recessive order, the alleles are
C, possibly ce, cch, and ca.
FULL PHEOMELANIN:
The [C-] genotype is the most common allele combination at the C locus. It allows for
full pheomelanin (gold) pigment
in the phenotype. Most Papillons are [CC] (a.k.a. [C-]) and therefore show regular gold coloring
in their coat.
UNDEFINED:
The ce is not clearly defined. It seems to have a lightening affect on
eumelanin pigment and it may be responsible for lightening skin pigmentation. But,
because light skin pigmentation is not considered desirable in many breeds, including the
Papillon, many breeders refrain from using them in their breeding programs. As a result,
there have not been enough matings to clearly identify the ce allele.
CHINCHILLA:
The cch, or chinchilla allele, dilutes the pheomelanin pigment into a
light cream or almost white color without affecting the eumelanin pigment. If a Pap
is sable [ay-] on the A locus (read above), then the Papillon will have
very pale gold hairs with normal black
hairs interspersed. This is what we call a lemon sable.
If the Pap is [ee] on the E locus (read below), the Papillon will have pale yellow/cream
hairs. These Paps are called lemon and
typically they are born white or an extremely pale shade of yellow/cream.
It does appear that the C allele is not fully dominant to the cch. Therefore, a [Ccch] genotype will
partially lighten the golden coat color into an intermediate shade of cream. The allele
combination, [cchcch], dilutes the golden hairs further into a
very light shade of cream that may appear almost white.
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EXAMPLE. . .
WHITE & LEMON SABLE
Throughout the coat, the hairs are a blonde or a cream color. There
are some black hairs.
EXAMPLE. . .
WHITE & LEMON
Throughout the coat, the hairs are a blonde or cream color.
There are no black hairs.
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ALBINO:
The most recessive allele on the C series is the ca,
which in the homozygous form, will produce complete albinism. An albino Papillon,
unlike one which simply has a white coat due to the S series, has no or very little
pigment in the hair, skin, and eyes. "The hair is white, the skin is a very light pink, and the
eyes, where the blood vessels on the retina provide the only color, are pink or red."
It is possible for the eyes to be blue and I know that human albinos can even
have brown eyes. Often an albino will have some vision problems. However,
albinism is extremely rare in all dogs, including the Papillon.
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Locus D = BLUE:
BLUE:
The D series is responsible for producing the color Maltese blue or silver, which is caused
by the dilution of both eumelanin and phaeomelanin pigment in dogs. Normal colored
dogs have the dominant [D-] genotype. Dogs with diluted coats have the [dd] genotype.
They also have lightened skin pigment and some have been known to have skin problems.
We know of only one documented case where a Papillon was this color, although we
have heard reports that there are a few others having been born. All of the
reported cases involved dogs from many years ago.
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Locus E = MASK, BRINDLE, EXTENTION, RED:
The E series has several alleles including Em, ebr, E, and e, and is rather complicated in nature
due to its interrelationship with the A series.
MASK:
To begin, the allele Em is responsible for the superextension of a black mask
on the Papillon’s face. The size of the mask is influenced by other factors that are
independent of the Em and the E series. In Papillons, the expression of the
mask can range from covering the entire head to only a little around the eyes, or around
the nose where there is usually a white nose band. When the Em allele
accompanies an As allele from the A series, the area affected by the mask
factor may appear even darker black. The minimal tricolor may be produced by the
genotype [atat Em-] which produces the
phenotype of a tricolor with a mask. If the mask is large enough it can cover some of the
tan or gold spots on the Papillon’s face. This would then explain why a minimal tricolor
Papillon lacks some of the tan spots on its face and but still has the tan spot under its tail.
Masks are most recognizable on a sable [ay-] Papillon and a large portion of
sable Papillons do have masks. Masks can also appear on liver dogs who are [bb] at
the B locus. However, their mask would be brown in color and it would be difficult to see,
considering that the rest of a liver Papillon's coat would also be brown.
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BRINDLE:
The allele ebr is responsible for the coat pattern brindle which Little
describes as being "difficult to analyze genetically" because of the "wide variations in its
expression and its interaction with the genes at the A locus" (Little 53). It appears evident that
brindle is not present in Papillons. In other breeds, brindle can be described as vertical
black stripes on a fawn or sable background. These stripes may be narrowed and
consequently darker due to the action of different modifiers. The stripes can also be brown
if the diluting gene, [bb], is present on the B locus. Sometimes the brindle color may be
hard to see and so some brindle dogs might be incorrectly identified as fawns or sables.
Because the Em allele for masks does not affect a dog’s body color, a dog
can be brindle and have a mask. Its genotype would be [Emebr].
Sometimes brindle colored dogs may also exhibit banded hairs.
However, the banding seems to be caused by the "A locus and not the brindle gene alone"
(Little 54). In relation to the A series, As is dominant to the brindle gene.
Therefore it takes [ebrebr] for the dog to be brindle if there is
at least one As allele present in the dog’s genotype. If there is no
As allele, the dog will be brindle with just one ebr allele.
Interestingly, when the genotype is [atat Eebr]
or [atat ebrebr] for the tricolor and
brindle phenotypes, the coat will be black where the tricolor gene directs it to be black,
but the otherwise tan points on the tricolor will have brindle markings.
EXTENTION:
The E allele does occur in Papillons and is relatively simple to explain. If a Papillon
is [E-], it will be whatever color the other genes express. The allele E does not produce
any color of its own; it just allows the coat colors from the other series to show.
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RED:
The last allele in the E series is e.
The [ee] genotype is epistatc which means that it will override whatever
gene is on the A locus.
In other words, a Pap who is [ee] will only show pheomelanin pigment in its coat
no matter what alleles are present on the A locus (which produces eumelanin or black hairs).
An [ee] Pap will not
show any eumelanin in the coat, though it will show eumelanin in the leather.
The shade of the gold hairs is determined by the C locus (read above) and by modifier
genes. As a result, the hairs on a red Pap may be anything from dark red or orange to pale yellow. Red Papillons
are typically born a pale shade of red that darkens with age.
If the dog is [atat ee] then it may “show lighter-yellow points against the
darker-red background” (Little 51).
Concerning the C locus, if the red, [ee], genotype is present along with the chinchilla factor,
[cchcch] (read above on the C locus), the Papillon develops a very pale shade of red called lemon. In
Papillons, lemon may also be referred to as a blonde. What is fascinating is that lemon
puppies are born pure white and the lemon color develops over the first few weeks of life,
like a Polaroid photograph.
A red Papillon will have black leather pigment. However,
although the
[ee] dogs show normal skin and eye color, they sometimes show reduced pigment in the
nose, especially in the winter known as snow nose (read below on snownose).
Something important to note
is that when I
interviewed breeders, the vast majority concurred that a red dog can have a black mask
(read above on masks).
However, analyzing Little’s work in the inheritance pattern of coat colors in dogs, it is
apparent that a red dog cannot have a black mask. For a dog to be red it must have the
genotype [ee]. For a dog to have a mask it must have the genotype [Em-].
Therefore, for there to be a red dog with a black mask, the dog would have to be [ee Em], which is not possible.
Another discrepancy that I found while interviewing countless
Papillon breeders, is that many of them believe that if a dog has no black on its body, but
does have a little black on the ears, that it is still a red. Unless there is a mutation,
which is extremely rare, this
does not seem possible. Therefore, these dogs are most likely sables (read above on sables)
that have very little black overlay.
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Locus G = GRAY
The G locus is responsible for graying or frosting in Papillons. A dog who is [gg] at the G locus
shows normal coloring throughout its life. It may grow some gray hairs when it is old, but
this has nothing to do with the G series. In dogs who are [GG] or [Gg] some of the dark
hairs are replaced by non-colored, or white, hairs. These new interspersed white hairs
cause the coat to appear faded. This lightening may start immediately after birth or after
several months, and it may stop after the dog has grown its adult coat or it may continue
throughout the dog’s life. There is also great variability in how much graying will occur.
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Locus K = BLACK
The color black is controlled by the K series. A dog who has at least one
K allele will be black in color regardless of what other alleles the dog has on
other loci. The only exception to this rule is that dogs who are bb on the B locus
will be brown, those that are dd on the D locus, will be blue, and those who are
ca ca on the C locus, will be albino. Other than these three
examples, dogs that are K- will be black in color. A who is homozygous recessive [kk]
will not be black. His color will be affected by all the other alleles.
Some Papillons may show red undertones in their coat. Others, might show red undertones above the eyes, on the cheeks, in
the ears, and under the tail. Sometimes these red tinted hairs will intensify with age
because the red tint is highlighted by sun exposure. The occurrence of this, however, is
relatively rare in Papillons. Although we haven’t found proof of a direct relationship with
coat color and Papillon ear fringe, w/black Papillons do seem to have more fringe than gold colored
Paps. This may be due to the protein structure of eumelanin which makes the hair stronger
and less likely to break.
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Locus M = MERLE:
The M locus is responsible for merle.
Dogs that are [mm] show a normal
distribution of color while [M-] dogs have "irregular blotches of dark (black or brown)
pigment against a distinctly lighter background of the same general basic pigment"
and with an increase in the amount of white spotting. The genotype [MM] has been associated with
producing an a dog with a lot of white that is deaf and/or blind and that is often sterile.
Although we have been told of merle Papillons, we have never seen one.
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Locus P = UNNAMED:
The P locus is not well established so it is not clear how or if it affects Papillons. It is
believed that there are two genes at this locus. Dominant P is responsible for normal
color. The genotype [pp] seems to be responsible for diluting eumelanin coat pigment
while having no affect on phaeomelanin pigment. In rodents, when black hairs are
diluted, a silver or lilac color is produced. While diluted browns have a silver-Champaign
or silver-fawn color. The occurrence of [pp] also seems to produce pink eyes.
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Locus T = TICKING:
The T locus is responsible for ticking or freckling.
The dominant allele, T, is responsible for
producing spots of color on a white background. The amount of ticking varies greatly.
On Papillons it usually occurs on the legs or muzzle. However, there have been Papillons
who have exhibited ticking over all the white regions of their coat. Interestingly, ticking is
not visible at birth. It usually demonstrates itself when the puppy several weeks of
age. (Dalmatians are affected with ticking which isn’t present at birth.)
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Locus R = ROAN:
The roan gene is has not been established. Roan is described
as scattered black hairs growing throughout the white coat areas.
Some dogs have been described as having both ticking and roan. However, not everyone is
convinced that roan is a separate gene from ticking. It is argued that roan is simply
very small spots of ticking. Others, however, do feel that it is a separate gene and that
it is caused by a
homozygous, recessive pairing of the [rr] alleles.
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CONCLUSION
The genes that are known to affect Papillons are as follows:
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| As |
B |
C |
D |
Em |
G |
m |
K |
P |
sp |
T |
| ay |
b |
cch |
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E |
g |
|
k |
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t |
| at |
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e |
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A review of what the various alleles do.
| Locus A | determines distribution of eumelanin and pheomelanin pigment |
| aw - | all the hairs on the coat are banded (not fully understood) |
| ay - | restricts eumelanin and distributes pheomelanin in random hairs |
| at - | distributes eumelanin throughout most of the coat; distributes pheomelanin at points |
| aa | distributes eumelanin over entire coat |
| Locus B | determines depth of eumelanin |
| B - | allows for full eumelanin pigment |
| bb | dilutes eumelanin into a brown shade; also dilutes leather into brown |
| Locus C | determines depth of pheomelanin |
| C - | allows for full pheomelanin pigment |
| ce - | undefined; possibly dilutes pheomelanin and leather |
| Cch - | dilutes pheomelanin into a lighter shade |
| cchcch | dilutes pheomelanin into an extremely pale shade |
| caca | completely restricts eumelanin and pheomelanin in coat, leather, and eyes; results in albinism |
| Locus D | determines depth of both eumelanin and pheomelanin |
| D - | allows for full eumelanin and pheomelanin pigment |
| dd | dilutes eumelanin and pheomelanin into a "blue" shade |
| Locus E | determines distribution of eumelanin |
| Em - |
distributes eumelanin as mask on face |
| E - |
distributes eumalanin throughout coat |
| ebr - |
distributes eumalanin in bands; results in brindle pattern |
| ee |
restricts eumelanin throughout coat; results in no black anywhere on coat |
| Locus G | determines distribution and depth of eumelanin and pheomelanin |
| G - | allows for full eumelanin and pheomelanin pigment |
| gg | restricts eumelanin and pheomelanin in random hairs; results in sporadic colorless hairs throughout coat |
| Locus K | determines distribution
of eumelanin |
| K - | distributes eumelanin over entire coat |
| kk - |
allows pheomelanin |
| Locus M | determines distribution and depth of eumelanin and pheomelanin |
| M - | responsible for blotched merle coloring |
| mm | allows for normal, uniform color production |
| Locus P | determines depth of eumelanin and pheomelanin |
| P - | allows for regular color depth |
| pp | reduces pigment depth; results in pink eyes |
| Locus S | determines distribution of nonpigmented (white) hairs |
| S - | allows for full pigment; no white |
| si - |
restricts pigment & allows white on muzzle, chest, underbelly, tail, and feet |
| sp - |
restricts pigment & allows white on chest, neck, legs, belly, loin area, and tail tip |
| swsw |
restricts pigment throughout coat & allows white on entire coat |
| Locus T | determines distribution of eumelanin or pheomelanin |
| T - | responsible for ticking on white areas of coat |
| tt | restricts ticking |
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