Inheritance of Coat Color

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THE INHERITANCE OF COAT COLOR IN THE SHAR-PEI : by J. E. James of James Genetics

The following text was originally published in the Chinese Shar-Pei Stud Book Number 3, printed 1983

This emerging rare breed will go through many changes before the stabilizes. Almost lost forever, this most ancient of breeds was saved from extinction by some very dedicated breeders. The color inheritance is complex now, but as more and more animals are imported and the breed becomes more popular, new colors will appear from long forgotten or lost gene complexes.

Black-Liver This most basic of all gene series is told by the color of the nose, lips, eye rims and foot pads. All dogs regardless of the actual coat color are either Black or Liver. Liver is recessive. A homozygous* (1) recessive liver animal will have all black coat color produced by the action of other genes changed to liver. Basic eye color in all dogs range from the deepest black - brown to amber, the recessive liver "points"* (2) gene will lighten whatever eye color the dog have, thus a liver pointed animal cannot have the deepest brown- black eyes. Black is dominant but a heterozygous* (3) animal carrying the recessive for liver will show a slight amount of incomplete dominance of the black over the liver. These dogs will show a rustiness or burned look to coat at seasonal changes or hormone change time. These shadings have no pattern and come and go with coat changes, some only showing at birth. This rustiness is only obvious in black coat colored animal--not being noticed on Yellow-Reds, etc.

Dilute This strong recessive changes everything and is the only gene complex capable of changing the basic color of the "Points" gene list above. Point color on a dog can change with the action of sunshine, frostbite, injury, illness, stress or diet. You may have noticed that a dog's nose will "go pink" the day before a show. Some of these changes are temporary and some permanent. Usually if, say a nose has been damaged, lip, eye rim and pad color remain to determine the true genotype of point color.

A black "Points" gene animal with recessive (homozygous) dilute will have all black points changed to a slate or dark blue. This coloration is so slight sometimes the animal only looks slightly "dusty". If black patterns are present, they are also changed to blue--thus, blue mask, blue trace marks, blue tipping and blue brindling.

A liver "Points" animal will have all liver changed to flesh or pinkish for the points and a flat Isabella* (4) or Weimaraner color in coat color. All patterns will be Isabella* (4) or Weimaraner colored including masking, tipping, etc. Dilute alters the color of fawns and reds--giving a strange flatness to colors. Linked to the dilute gene is a blazing eye color ranging from the lightest watery hazel- blue to flaming yellow. A dark eye cannot occur in the dilute animal. This dilute series of genes is very prevalent in breeds coming down from the original "temple dogs." Breeders in the Shar-Pei have not reported this series but it could occur or already has without being noticed. ( The first identified blue dog appeared in 1985*)

Yellow-Red* (5) Two different types of yellow-red occur in the Shar-Pei. Both are recessive to pure all over black. The interaction of these two series of genes is complex and hard to understand. Black can be produced by breeding a dog from one type of yellow--red to a dog from the other yellow-red making it appear that the black is recessive is not. In this breeding, each series loses something allowing black to occur. ( See Color Inheritance in the Dog by Little.)

Sable Yellow-Red This shimmering shaded color is a popular color in the breed. ( It no longer is because of the inability of a conformation judges to determine if it is sable or patterned). Dogs of this color can be born pure black and , when the hair grows, be a rich sable. Dogs can be born a creamy white and darken over. Sable is changeable--some animals changing all their lives. Sable red allows all the colorful patterns to show fully on the Shar-Pei. Black masks, black tipping, black trace marks, or possible black brindling. If a liver point gene is present, no black can occur--thus, liver masks, liver tippings and liver trace. Sable dogs can be colored by the actions of the patterns or not. Sable dogs can be showing a full mask, full brindlings, full trace marks or full tipping will be a true sable animal, however.

Extension Yellow-Red This series is also present in the Shar-Pei. A dog is much more evenly colored. He will not change as much from birth as sable. Extension Yellow-Red is a strong series. Extension animals will not show any signs of patterns--thus no masking, no tipping, no traces, or no brindling. Sometimes only by breeding can you tell which type of yellow-red occurs in your animal.
A Yellow-Red dog from either series can either be black pointed or liver nose "pointed". The liver point gene does not change the color of the Yellow-Red. Patterns will occur in Liver, however, instead of black,, giving liver masking, tipping traces or brindling.

Color and Paling These two series of genes work somewhat together giving the multitude of shades in both types of Yellow-Reds listed before--also they give the shades of color in the pure chocolates. they do not affect pure black or pure white. In the Yellow-Reds, the color of the Shar-Pei can range from almost a pure white-cream to a dark Irish Setter red mahogany. The sables can have the pattern gene-- the extensions cannot.

In general--the lightest, palest colors are more recessive and the darker, clearer ones are most dominant. In the chocolates, the color can range from beige to Hershey color.

Agouti ( Wolf or Wild Coloration) In the sable series of colors, this is recessive to pure black and sable Yellow-Red. A lovely gray banded coloration with silver trim. This is the soft blue -silvers in the Afghan and the beautiful blues in the Shih-Tzu. This series allows full color in the points--so black and pure liver points remain with full eye color. Dogs are born with this coloration. All pattern genes show, thus, a blue with a black mask or blue brindle can occur. With liver points, a soft banded beige gray with liver patterns could occur.

Black and Tan or Tan Pointed A trouble maker in many self colored breeds. The allele* (6) of the Yellow-Red series hides for many generations, making itself known as a complete surprise in the whelping box. This has remained to trouble Weimaraners, Poodles, Labradors, Great Danes, and many, many others. Tan pointed allele is recessive to black, sable , Yellow-Red, Agouti-Grey, and has a strange epistasis* (7) with the extension of Yellow-Red.

Tan pointed animals have colorful tan pointed trim in the following specific places: sides of muzzle, above eyebrows, under throat latch, inside the ears, butterfly on chest, all four boots, around vent and under tail. This tan pointed trim can range in color from almost silver to deepest red mahogany depending on color and paling genes. Tan points are not in the same spot on the series inheritance as the sable Yellow-Red but occur with the extension Yellow-Red, however, are not obvious except to deepen the color somewhat. Tan points occur in the black pointed animal or a liver pointed animal. In the liver, they are referred to usually as red and tan. Tan pointed animals being in the sable Yellow-Red series, can also have all the colorful patterns. Thus black mask can wipe out some of the head tan, black tippings can cover some of the muzzle, throat and chest trim and brindle can brindle all the tan pointed areas completely--giving a black brindle so desired in breeds like the Boston Terrier.

Patterns There is much disagreement with color geneticists as to just how these are inherited but all agree the only color animals colored primarily from the sable Yellow-Red series--thus sable Yellow-Reds, Agouti ( wild ) or tan pointed animals can have these patterns. If an animal has both types of Yellow-Red, a small amount of pattern genes could show--mask just beyond the end of the muzzle or a slight "ghost brindling". Pure extension Yellow-Red will not have these patterns.

Black Mask Dominant and factored. Ranging from none to fully covering the whole head and ears. A mask giving expression to face and zIng to nose rolls is desirable in the Shar-Pei. It gives much expression to eyes and accents ears. Too much masking in the breed however could be undesirable. If a liver point gene is present, masking will occur in liver color.

Black Tipping ( Or liver tipping if Liver Point) Black will tip and color tips of hair.

Black Trace ( Or liver Trace if Liver Points) Black will tip and color trace mark on head and midline.

Brindle It comes down from lines of extension Yellow-Red or Blacks as a true sable Yellow-Red cannot carry it without showing. Brindle needs a lovely base color from the sable overlay with many degrees of tiger striping ranging from a few pencil lines to a zebra pattern. Agouti also makes a lovely base for brindle as in the Irish Wolfhounds. Brindle is dominant and can occur with or without black masking, etc. If a liver point gene is present, all brindle will occur in liver over fawn colorations

Black and Liver--Chocolate. This series is a combination of the dominant allele from the sable Yellow-Red series and dominant black occurs. If a liver point gene is present, a true all over chocolate animal occurs. Black and Liver-Chocolate can and do carry any and all of the other Shar-Pei colors in the recessive--making a clean, all over black or chocolate coloration very hard to get. As with all good dominants, the dominant Black and dominant Liver-Chocolate are hard to get and keep. Recessives keep cropping up to slightly influence the dominant color, giving off shadings, rustiness, etc. Test breeding your blacks into Chocolate lines could keep the liver point gene from making an appearance. But test breeding into fawn lines might not prove anything--one breeding might show all black but bred to a different type of fawn-red will recover some fawns. Pure black lines will be established in the future--also pure chocolate lines as in the Poodle--but this is a long time away. Black is not colored by the actions of color and paling genes, but chocolate is. Chocolates bred into the fawn lines might produce whole litters of liver pointed puppies (fawn) that will lack the expression that black points will give them. Chocolates also will have to keep extremely dark eyes in their lines as the liver point gene lightens the eyes. If a light eye is used to begin with, from a black dog, light yellow eyes could be produced. Deep amber is the eye color to strive for in the chocolates. Dark coat also must be considered in the chocolates as a light coat color could look "dead grassy" or dirty. Black or pure chocolates produced by breeding two Yellow-Reds (fawns) together will carry recessives for both types of Yellow-Red.

White Spotting A major problems in almost every registered breed on earth. It has been said that not a dog alive anywhere does not have some white hairs somewhere. White spotting is so important in all breeds. Some depend on it for their "flash", some need the symmetry of white spotting, some desire the rakishness it gives, many others just tolerate a small amount of it and some brand it a "no-no" under all conditions.

All White Spotting is Recessive This must be remembered in all breedings. Geneticists have argued about this inheritance forever. Author, Little, lists it as one big sliding inheritance. Whitney divides in into at least two series. Others list many alleles of the same series. I will list it as I have observed it in over 500 breedings working with it. There seems to be some crossover between these two series, however.

Self and Irish Spotting. Starts out as a few chest hairs or white under pastern. Develops more chest spotting, white climbing up the foot to the nail bed, white on belly and penis sheath, white under neck, white spreads around neck, above nail into boots, belly, then starts to color head, then muzzle, tail tip. This series seems to be symmetrical--if one part of the body gets white, the other somewhat mirrors it. Seems to end with white crossing flank and hocks with full white collar, body, tail and symmetrical head markings, four boots mimicking a Boston Terrier. Factors or modifiers seem to be the key to how much white. To reduce this breed away from it. White recessives can soon saturate a breed.

Piebald.. A big problem series. Can be carried unknown by a fully colored dog to appear in offspring when doubled up. Piebald breaks up the body into spots. It is more of a wild type of spotting, not following the symmetry of the Self and Irish Spotting. A small amount of Piebald or a large amount of Piebald can be carried by fully colored animals. When they double up, you will determine how much the parents are carrying. Piebald gains in white in the following manners: uneven markings appear on the chest, uneven boots (one fully colored, three white, etc.) rakish half head markings, rings around eye, fully colored head with body losing color until only one or two body spots are left. One of the last placed for the body to lose color is behind the midline or root of tail. Head is the next place to lose color until perhaps just one ear is left colored. "When the inner ear is without pigment in some breeds from the action of the Piebald gene--as in Dalmatians and Bull Terriers, sometimes the animal is deaf." This study goes on in these breeds as this theory is just one suggested by researchers. The full Piebald white is firmly established in the Shar-Pei breed and must be considered in all breedings. In all white spotting, any color appearing besides the white will be the color the dog would have been if he were not white spotted. This includes "ticks" and "roans", thus a Yellow-Red dog with black tipping will be fawn with black tipping on his spots. If white hits where a black mask would be this tick or freckle there will black, etc.

Ticking ..Dominant and factored. It ranges from freckles to fully spotting the areas of white

Roan Recessive and factored. It ranges from a few flecks to spotting covering all areas of white.

Greying with Age As in Blue and Old English. It is not known if this breed has these genes. It is dominant.

Merle A ragged torn coloration which must have liver or black on which to work well. Doubled up, it produces a type of dominant defective animal with serious defects. Shar-Pei do not have this type of white.