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The coat of a dog is the fur that covers its body.

Newfoundland lying next to its combed-out seasonal undercoat.

A dog coat may be a double coat, made up of a soft undercoat and a coarse topcoat, or a single coat, without an undercoat. The terms fur and hair are often used interchangeably when describing dog coats, but in general, a double coat, such as that of the Newfoundland, is called a fur coat, while a single coat, such as the poodle's coat, may be called a hair coat.

Colours, patterns, textures

There is a greater variety of coat colours and patterns found in domestic (tame) dogs than in the wild wolf, even though dogs and wolves are of the same genus. Coat colours in dogs were not likely initially selected for by humans but "were probably inadvertent outcomes of some other process...early selection for tameness.^[1] Research has found that tameness brings associated inherited changes, especially in coat colours and patterns.^[2]^[3]

Domestic dogs often display the remnants of counter-shading, a common natural camouflage pattern. The general theory of counter-shading is that when the animal is lit from above, it will appear lighter on its lower half and darker on its upper half, so that when observed from either above or below, it will blend in with the natural background. This type of natural camouflage is most apparent in birds and fish.^[4]^[5]

Genetic basis

Modern breeds of dog exhibit a diverse range of coat colourings, patterns, lengths and textures. In recent years, the understanding of the genetic basis for coat colouring and patterning^[6] and coat length and texturing^[7] has increased significantly.

There are currently eight known genes within the canine genome that are associated with coat colour. Each of these genes occurs in at least two variants, or alleles, which accounts for the variation in coat colour between animals. Each of these genes exists at a fixed location, or locus, of the animal's genome. The loci associated with canine coat colour are:

A (agouti) locus

The alleles at the A locus are related to the production of agouti signalling protein (ASIP) and determine whether an animal expresses an agouti appearance, and if so what type, by controlling the distribution of pigment in individual hairs. There are five suspected alleles that occur at the A locus:

a^w = Wild-type agouti (cream to red hair with black tips)
A^y = Fawn (cream to red hair with darker tips) or sable (solid black hairs interspersed amoungst lighter reddish hairs)
A^s = Saddling
a^t = Tan points; Tricolours
a = Recessive black (inhibition of phaeomelanin)

Most texts suggest that the dominance hierarchy for the A locus alleles appears to be as follows: A^y > A^s > a^w > a^t > a, however research suggests the existance of pairwise dominance/recessive relationships in different families and not the existance of a single hierarchy in one family.^[8] This means, for example, that A^s may be incompletely dominant over a^t.

B (brown) locus

The alleles at the B locus are related to the production of tyrosinase related protein 1 (TYRP1) and determine the degree to which an animal expresses tyrosinase, a brown-black protein related to the production of melanin, in its coat and skin (including the nose and paw pads). There are two known alleles that can occur at the B locus:

B = Black
b = Brown (includes several alleles - b^s, b^d and b^c)

B is dominant to b. An animal that is has at least one copy of the B allele will have a black nose, paw pads and eye rims while an animal that is homozygous for any of the b alleles will have a liver nose, paw pads and eye rims.

D (dilute) locus

The alleles at the D locus (the melanophilin gene or MLPH) are related to the dilution of eumelanin and/or phaeomelanin and determine the intensity of pigmentation. There are two known alleles:

D = Not Diluted
d = Diluted (Black becomes grey or blue; brown becomes light tan or "Isabella")

D is dominant to d. Homozygosity of d is sometimes accompanied by hair loss and recurrent skin inflammation, a condition referred to as either color dilution alopecia (CDA) or black hair follicular dysplasia (BHFD) depending upon the breed of dog.^[9]

E (extension) locus

The alleles at the E locus (the melanocortin receptor 1 gene or MC1R) determines whether an animal expresses a melanistic mask or a grizzle overlay, as well as determining whether an animal expresses eumelanin in it's coat. Expression of eumelanin will result in a black or brown coat, while a lack of expression of eumelanin will result in a red or yellow coat. There are four known alleles that occur at the E locus:

E = No mask, animal expresses eumelanin (coat will be black or brown)
E^G = Grizzle (dark overlay covering the top and sides of the body, head and tail, and the outside of the limbs)
E^m = Mask, animal expresses eumelanin (coat will be black or brown)
e = No mask, animal does not express eumelanin (coat will be red or yellow)

The dominance hierarchy for the E locus alleles appears to be as follows: E^m > E^G > E > e. The Grizzle allele is specific to Salukis and Afghan Hounds, the latter in which it is refered to as "Domino". The expression of E^G is dependant upon the animal being homozygous for a^t and not possessing E^m or K^B.^[10] An animal that is homozygous for e will express a red or yellow coat regardless of the alleles at other loci (unless the animal is homozygous for c^a at the C locus in which case it will be albino).

H (harlequin) locus

DNA studies have not yet isolcated the gene at the H locus, but the traits associated with it have been mapped to chromosome 9.^[11] The H locus is a modifier locus (of the M locus) and the alleles at the H locus will determine if an animal expresses a harlequin pattern (white base with black patches). There are two alleles that can occur at the H locus:

H = Harlequin
h = Non-harlequin

H is dominant to h. Breeding data suggests that H is embryonic recessive lethal and that therefore all harlequins are H/h.^[11] The Harlequin allele is specific to Great Danes. As H is a modifier locus of the M locus, in order for the Harlequin pattern to be expressed, one copy of the H allele (at the H locus) and one copy of the M allele (at the M locus) must be present (ie. H/h and M/m).

K (dominant black) locus

The alleles at the K locus (the β-Defensin 103 gene or DEFB103) determine the colouring pattern of an animal's coat.^[12] There are three known alleles that occur at the K locus:

K^B = Solid colouring (does not mean than white markings can not appear)
k^br = Brindle
k^y = Enables the expression of agouti alleles that require the expression of phaeomelanin

The dominance hierarchy for the K locus alleles appears to be as follows: K^B > k^br > k^y. The colouring of an animal that posseses at least one K^B will be determined by the alleles it posses at the B and E loci. An animal with one k^br allele and no K^B allele will express a brindle pattern to it's coat. An animal that is homozygous for k^y will express the agouti pattern in accordance with the alleles it has at the A locus.

M (merle) locus

The alleles at the M locus (the SILV gene) determine whether an animal expresses a merle pattern to it's coat (patches of sporadic coloured and white hairs and other patches of solid colour). There are two alleles that can occur at the M locus:

M = Merle (visible in dogs that are not e/e)
m = Non-merle

M is dominant to m. Both heterozygosity and homozygosity of the merle gene (i.e. M/m and M/M) are linked to a range of auditory and ophthalmologic abnormalities.^[13]

S (spotting) locus

The alleles at the S locus (the microphthalmia-associated transcription factor gene or MITF) determine the degree and distribution of spotting of an animal's coat.^[14] There is disagreement as to the number of alleles that occur at the S locus, with researchers postulating either two^[15] or four^[16] alleles. The four alleles postulated are:

S = Solid colour (small areas of white may appear on chest, toes or tail tip)
sⁱ = Irish-spotting (white on muzzle, forehead, feat, legs, chest and tail)
s^p = Pie-bald spotting (large areas of white)
s^w = Extreme pie-bald spotting (Extremely large areas of white, almost completely white)

S is dominant to s. DNA studies have not yet confirmed the existance of all four alleles, with some research suggesting the existance of at least two alleles (S and s^p)^[14] and other research suggesting the possible existence of a third allele (sⁱ).^[17] It has been suggested that what appears to be the result of an s^w allele is in fact the result of plus and minus modifiers acting on one of the other alleles.^[14] It is thought that the spotting that occurs in Dalmatians is the result of the interaction of three loci (the S locus, the T locus and F locus) giving them a unique spotting pattern not found in any other breed.^[18]

Postulated Loci

There are at least four additional theoretical loci thought to be associated with coat colour in dogs. DNA studies are yet to confirm the existance of these genes or alleles but their existance is theorised based on breeding data:^[19]

C (coloured) locus

The alleles at the theoretical C locus are thought to determine the degree to which an animal expresses phaeomelanin, a red-brown protein related to the production of melanin, in its coat and skin. Five alleles are theorised to occur at the C locus:

C = Anaimal expresses phaeomelanin (full coloured)
c^ch = Partial inhibition of phaeomelanin (decreased red pigment)
c^d = Complete inhibition of phaeomelanin, producing a white coat
c^b = Partial inhibition of phaeomelanin, causing a pale "blue" coat (as in dilution) and blue eyes
c^a = Complete inhibition of all melanin production (albino)

It is thought that an animal that is heterozygous for the C allele with one of the non-albino alleles (i.e. C/c^ch, C/C^d or C/c^b) will express a result somewhere between the two alleles.^[20]

G (progressive greying) Locus

The alleles at the theoretical G locus are thought to determine if premature greying of the animal's coat will occur. Two alleles are theorised to occur at the G locus:

G = Premature greying
g = No premature greying

It is thought that G is dominant to g.

I (intensity) Locus

The alleles at the theoretical I locus are thought to affect phaeomelanin expression. Two alleles are theorised to occur at the I locus:

I = Intense red, not diluted
i = Not intese red

It is thought that I and i are co-dominant, so that animals with i/i will be paler than animals with I/i.

T (ticking) locus

The alleles at the theoretical T locus are thought to determine whether an animal displays small, isolated regions of pigment in otherwise white regions (not apparent on non-white animals). Two alleles are theorised to occur at the T locus:

T = Ticked
t = Not ticked

It is thought that T is dominant to t.

Colour names

Brown Chesapeake Bay Retriever		Brown and its variants, including mahogany, midtone brown, gray-brown, blackish brown; the Chesapeake Bay Retriever, whose colour "must be as nearly that of its working surroundings as possible", also uses the terms sedge and deadgrass.
Red Irish Setter	Dark chocolate Australian Kelpie	Red—reminiscent of reddish woods such as cherry or mahogany—and its variants, including chestnut, tawny, orange, roan, rust, red-gold, reddish brown, bronze, cinnamon, tan, ruby; also includes liver, a reddish brown somewhat the colour of cinnamon or bronze; the breed often determines whether "liver", "chocolate", "brown", or "red" is used to describe the colour, as in a liver German Shorthaired Pointer or a chocolate Labrador Retriever.
File:Toy poodle.jpg Apricot Poodle	Dark Golden Retriever	Gold Rich reddish-yellow, as in a Golden Retriever, and its variants, including yellow-gold, lion-coloured, fawn, apricot, wheaten (pale yellow or fawn, like the colour of ripe wheat), tawny, straw, yellow-red, mustard, sandy, honey.
Yellow mixed-breed dog	Yellow Labrador Retriever	Yellow—yellowish-gold tan, as in a yellow Labrador Retriever—and its variants, including blond and lemon. Lemon is a very pale yellow or wheaten colour which is not present at birth (the puppies are born white) but gradually becomes apparent, usually during the first six months of life.
Cream French Bulldog		Cream: Sometimes it's hard to define the line between pale yellow and cream. Depending on the breed and individual, cream ranges from white through ivory and blond, often occurring with or beneath lemon, yellow, and sable.
Black Newfoundland	Black Labrador Retriever	Black: Usually pure black but sometimes grizzled, particularly as dogs age and develop white hairs, usually around the muzzle.
File:Kerry blue Terrier.jpg Kerry Blue Terriers	Blue merle Australian Shepherd	Blue: Not the rainbow's blue but rather a dark metallic gray, often as a blue merle or speckled (with black). Kerry Blue Terriers, Great Danes, Australian Silky Terriers, Bearded Collies, and Australian Shepherds are among many breeds that come in blue.
Silver gray Weimaraner	Salt and pepper gray Miniature Schnauzer	Gray—sometimes also called blue—and its variants, including pale to dark gray, silver, pepper, grizzle, slate, blue-black gray, black and silver, steel, lavender, silver-fawn.
White American Eskimo Dog	White Bichon Frisé	White: Such a light cream that it is seen and described as pure white, making them distinct from albino dogs. A white dog, as opposed to an albino one, has dark pigment around the eye rims and nose, often coupled with dark-coloured eyes. There is often some coat identifiable as cream between the dog's shoulder blades.

Patterns

Patterns, like colours, might be called by different terms for different breeds.

Liver and tan Australian Kelpie	Black and Tan Coonhound	Black and tan, liver and tan, blue and tan: Coat has both colours but in clearly defined and separated areas, usually with the darker colour on most of the body and tan (reddish variants) underneath and in highlights such as the eyebrows. Black and brindle and liver and brindle, in which the same pattern is evident with brindling in place of tan, are also possible, but less common.
Black and white Border Collie	Blenheim (Red-brown and white) Cavalier King Charles Spaniel	Bicolor (also called Two-color, Irish spotted, Flashy, Patched, Tuxedo) Any color or pattern coupled with white spotting. This can range anywhere from white toes and tail tip to a mostly-white dog with color around the base of the ears and tail. Some breeds have special names for the colour combinations; for example, Cavalier King Charles Spaniel uses Blenheim for reddish brown (chestnut) and white. Irish Spotted or flashy pattern is symmetrical and includes a white chest, white band around the neck, white belly, and white feet or "boots." This pattern is commonly seen in herding dogs, and Boxers, among others.
Black tricolour Entlebucher Mountain Dog	Tricolour Beagle	Tricolour: Three clearly defined colours, usually either black, liver, or blue on the dog's upper parts, white underneath, with a tan border between and tan highlights; for example, the Smooth Collie, the Rough Collie, the Papillon,or the Sheltie. Tricolour can also refer to a dog whose coat is patched, usually two colours (such as black and tan) on a white background.
Blue merle tricolour Australian Shepherd	Red merle Catahoula Leopard Dogs	Merle: Marbled coat with darker patches and spots of the specified colour. Merle is referred to as "Dapple" with Dachshunds.
Tuxedo mixed-breed dog.	Tuxedo mixed-breed	Tuxedo: Solid (usually black) with a white patch (shirt front) on the chest and chin, and white on some or all of the feet (spats.) Common colouration in Labrador mixes that may stem from the St. John's Water Dog ancestral breed.
Harlequin Great Dane		Harlequin: "ripped" sploches of black on white. Only the Great Dane exhibits this coat pattern.
Spotted Dalmatian		Spotted Most often dark pigmented spots on a light background. The spotting on dalmatians is unique as it involves mutations in at least three different spotting genes
Red-speckled Australian Cattle Dog	Liver-ticked German Shorthaired Pointer	Flecked, ticked, speckled: also called belton in English Setters
Orange belton (orange and white speckled) English Setter	Blue speckled Australian Cattle Dog
Darker brindle and white Boston Terrier	Medium brindle Galgo Español	Brindle: A mixture of black with brown, tan, or gold; usually in a "tiger stripe" pattern.
Airedale Terrier with large black saddle		Saddle or blanket: A different colour, usually darker, over the center of the back.
Dark orange sable Pomeranian	Lighter sable Shetland Sheepdogs	Sable: Black-tipped hairs; the background colour can be gold to yellow, silver, gray, or tan. The darkness of the coat depends on how much of each hair is black versus the lighter colour.

Texture

Texture, like colour and pattern, might be called by different terms for different breeds, even when referring to the same quality of coat. Some terms used to describe dog coat texture are smooth, rough, curly, straight, broken, and silky.

Coat textures vary tremendously. Densely furred breeds such as most sled dogs and Spitz types can have up to 600 hairs per inch, while fine-haired breeds such as the Yorkshire Terrier can have as few as 100, and the "hairless" breeds such as the Mexican Hairless and the Peruvian Inca Orchid have none on parts of their bodies. The texture of the coat often depends on the distribution and the length of the two parts of a dog's coat, its thick, warm undercoat (or down) and its rougher, somewhat weather-resistant outer coat (topcoat, also referred to as guard hairs). Breeds with soft coats often have more or longer undercoat hairs than guard hairs; rough-textured coats often have more or longer guard hairs. Textures include:

Double-coated: Having a thick, warm, short undercoat (or down) that is usually dense enough to resist penetration by water and a stronger, rougher weather-resistant outer coat (topcoat), also referred to as guard hairs. Most other coat types are also double-coated.
Single-coated: Lacking an undercoat.
Smooth-coated: "Smooth" to the eye and touch.
Wire-haired: Also called broken-coated. The harsh outer guard hairs are prominent, providing excellent weather protection for hunting dogs such as the Border Terrier or Wirehaired Pointing Griffon.
Long-haired: Hair longer than an inch or so.
Short-haired: Hair around an inch or so long.
Corded coat: for example, see Puli

Show coats

The nature and quality of a purebred dog's coat is important to the dog fancy in the judging of the dog at conformation shows. The exact requirements are detailed in each breed's breed standard and do not generalise in any way, and the terminology may be very different even when referring to similar features. See individual breed articles for specific information.

Shedding

Every hair in the dog coat grows from a hair follicle, which has a cycle of growing, then dying and being replaced by another follicle. When the follicle dies, the hair is shed (moults). The length of time of the growing and shedding cycle varies by breed, age, and by whether the dog is an inside or outside dog.

Many dogs shed their undercoat each spring and regrow it again as colder weather comes in; this is also referred to as blowing the coat. Many domesticated breeds shed their coat twice a year. In some climates, the topcoat and undercoat might shed continuously in greater and smaller quantities all year.

Hypoallergenic coats

Some dog breeds have been promoted as hypoallergenic (which means less allergic, not free of allergens) because they shed very little. However, no canine is known to be completely nonallergenic. Often the problem is with the dog's saliva or dander, not the fur.^[21] Although poodles and terriers (and mixes of poodles and terriers) are commonly represented as being hypoallergenic, the reaction that an individual person has to an individual dog may vary greatly. In treating dog related allergies, it has been found that "Factors related to individual dogs seem to influence the allergenicity more than breed..."^[22]

References

^ The Domestic Dog By James Serpell, page 37, Cambridge University Press 1995, 2002, ISBN o521415292
^ Trut, Lyudmila N (1999). "Early Canid Domestication: The Farm-Fox Experiment" (PDF). American Scientist. 87 (2): 160–169.. (A Russian study of pedomorphosis in a 40-year breeding program to domesticate red foxes.)
^ Uncovering the genetic basis for tameness - a research strategy F. W. Albert Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, 2008 (PDF file)
^ Klappenbach, Laura (2008). "What is Counter Shading?". About.com. Retrieved 2008-10-22.
^ Cunliffe, Juliette (2004). "Coat Types, Colours and Markings". The Encyclopedia of Dog Breeds. Paragon Publishing. pp. 20–3. ISBN 0752582763.
^ Schmutz, S. M. & Berryere, T. G. (2007). "Genes affecting coat colour and pattern in domestic dogs: a review". Animal Genetics. 38 (6): 539–549. doi:10.1111/j.1365-2052.2007.01664.x. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ Edouard Cadieu, Mark W. Neff, Pascale Quignon, Kari Walsh, Kevin Chase, Heidi G. Parker, Bridgett M. VonHoldt, Alison Rhue, Adam Boyko, Alexandra Byers, Aaron Wong, Dana S. Mosher, Abdel G. Elkahloun, Tyrone C. Spady, Catherine André, K. Gordon Lark, Michelle Cargill, Carlos D. Bustamante, Robert K. Wayne, Elaine A. Ostrander (2009). "Coat Variation in the Domestic Dog Is Governed by Variants in Three Genes". Science. 326 (5949): 150–153. doi:10.1126/science.1177808. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ Julie A. Kerns, J. Newton, Tom G. Berryere, Edward M. Rubin, Jan-Fang Cheng, Sheila M. Schmutz and Gregory S. Barsh (2004). "Characterization of the dog Agouti gene and a nonagouti mutation in German Shepherd Dogs". Mammalian Genome. 15 (10): 798–808. doi:10.1007/s00335-004-2377-1. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ Ute Philipp, Henning Hamann, Lars Mecklenburg, Seiji Nishino, Emmanuel Mignot, Anne-Rose Günzel-Apel, Sheila M Schmutz & Tosso Leeb (2005). "Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs". BMC Genetics. 6 (34). doi:10.1186/1471-2156-6-34. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)
^ Dayna L. Dreger & Sheila M. Schmutz (2010). "A New Mutation in MC1R Explains a Coat Color Phenotype in 2 Old Breeds: Saluki and Afghan Hound". Journal of Heredity. 101 (5): 644–649. doi:10.1093/jhered/esq061. {{cite journal}}: Unknown parameter |month= ignored (help)
^ ^a ^b Leigh Anne Clark, Alison N. Starr, Kate L. Tsai & Keith E. Murphy (2008). "Genome-wide linkage scan localizes the harlequin locus in the Great Dane to chromosome 9". Gene. 418 (1–2): 49–52. doi:10.1016/j.gene.2008.04.006. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ Sophie I. Candille, Christopher B. Kaelin, Bruce M. Cattanach, Bin Yu, Darren A. Thompson, Matthew A. Nix, Julie A. Kerns, Sheila M. Schmutz, Glenn L. Millhauser, Gregory S. Barsh (2007). "A β-Defensin Mutation Causes Black Coat Color in Domestic Dogs". Science. 318 (5855): 1418–1423. doi:10.1126/science.1147880. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ Leigh Anne Clark, Jacquelyn M. Wahl, Christine A. Rees & Keith E. Murphy (2006). "Retrotransposon insertion in SILV is responsible for merle patterning of the domestic dog". PNAS. 103 (5): 1376–1381. doi:10.1073/pnas.0506940103. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ ^a ^b ^c Sheila M. Schmutz, Tom G. Berryere & Dayna L. Dreger (2009). "MITF and White Spotting in Dogs: A Population Study". Journal of Heredity. 100 (Suppliment 1): 566–574. doi:10.1093/jhered/esp029. {{cite journal}}: Unknown parameter |month= ignored (help)
^ Winge, Ojvind (1950). Inheritance in Dogs: With Special Reference to the Hunting Breeds. Catherine Roberts (translator). Ithaca, N.Y.: Comstock Publishing. p. 194.
^ Little, Clarence Cook (1957). The Inheritance of Coat Color in Dogs. New York: Comstock Publishing. p. 194. ASIN B0007DYSH6.
^ Karlsson E. K., Baranowska I., Wade C. M., Salmon Hillbertz N. H., Zody M. C., Anderson N., Biagi T. M., Patterson N., Pielberg G. R., Kulbokas E. J. III, Comstock K. E., Keller E. T., Mesirov J. P., von Euler H., Kämpe O., Hedhammar A., Lander E. S., Andersson G., Andersson L., Lindblad-Toh K. (2007). "Efficient mapping of mendelian traits in dogs through genome-wide association". Nature Genetics. 39 (11): 1304–1306. doi:doi:10.1038/ng.2007.10. {{cite journal}}: Check |doi= value (help); Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
^ Edward J. Cargill1, Thomas R. Famula, Robert D. Schnabel, George M. Strain & Keith E. Murphy (2005). "The color of a Dalmatian's spots: Linkage evidence to support the TYRP1 gene". BMC Veterinary Research. 1 (1). doi:10.1186/1746-6148-1-1. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link) CS1 maint: unflagged free DOI (link)
^ Sheila M. Schmutz (December 27, 2008). "Coat Color Alleles in Dogs". Retrieved September 12, 2010.
^ Pamela A. Davol (January 29, 2001). "B/b, E/e, and Beyond: A Detailed Examination of Coat Color Genetics in the Labrador Retriever". Retrieved September 11, 2010.
^ "Nonallergenic Dog? Not Really" by Denise Grady, New York Times, 5 Feb 1997
^ Heutelbeck ARR, Schulz T, Bergmann K, Hallier E (2008). "Environmental Exposure to Allergens of Different Dog Breeds and Relevance in Allergological Diagnostics". Journal of Toxicology and Environmental Health, Part A. 71 (11–12): 751–8. doi:10.1080/15287390801985513. PMID 18569573. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

Cunliffe, Juliette (2004). "Coat Types, Colours and Markings". The Encyclopedia of Dog Breeds. Paragon Publishing. pp. 20–23 and various.
Fogle, Bruce (2000). "The Breed Section Explained". The New Encyclopedia of the Dog. Dorling Kindersley. p. 83 and various. ISBN 0751304719.

External links

[1] The Domestic Dog By James Serpell, page 37, Cambridge University Press 1995, 2002, ISBN o521415292

[2] Trut, Lyudmila N (1999). "Early Canid Domestication: The Farm-Fox Experiment" (PDF). American Scientist. 87 (2): 160–169.. (A Russian study of pedomorphosis in a 40-year breeding program to domesticate red foxes.)

[3] Uncovering the genetic basis for tameness - a research strategy F. W. Albert Department of Evolutionary Genetics, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany, 2008 (PDF file)

[About.com-4] Klappenbach, Laura (2008). "What is Counter Shading?". About.com. Retrieved 2008-10-22.

[Encyclopedia_of_Dog_Breeds-5] Cunliffe, Juliette (2004). "Coat Types, Colours and Markings". The Encyclopedia of Dog Breeds. Paragon Publishing. pp. 20–3. ISBN 0752582763.

[6] Schmutz, S. M. & Berryere, T. G. (2007). "Genes affecting coat colour and pattern in domestic dogs: a review". Animal Genetics. 38 (6): 539–549. doi:10.1111/j.1365-2052.2007.01664.x. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[7] Edouard Cadieu, Mark W. Neff, Pascale Quignon, Kari Walsh, Kevin Chase, Heidi G. Parker, Bridgett M. VonHoldt, Alison Rhue, Adam Boyko, Alexandra Byers, Aaron Wong, Dana S. Mosher, Abdel G. Elkahloun, Tyrone C. Spady, Catherine André, K. Gordon Lark, Michelle Cargill, Carlos D. Bustamante, Robert K. Wayne, Elaine A. Ostrander (2009). "Coat Variation in the Domestic Dog Is Governed by Variants in Three Genes". Science. 326 (5949): 150–153. doi:10.1126/science.1177808. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[8] Julie A. Kerns, J. Newton, Tom G. Berryere, Edward M. Rubin, Jan-Fang Cheng, Sheila M. Schmutz and Gregory S. Barsh (2004). "Characterization of the dog Agouti gene and a nonagouti mutation in German Shepherd Dogs". Mammalian Genome. 15 (10): 798–808. doi:10.1007/s00335-004-2377-1. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[9] Ute Philipp, Henning Hamann, Lars Mecklenburg, Seiji Nishino, Emmanuel Mignot, Anne-Rose Günzel-Apel, Sheila M Schmutz & Tosso Leeb (2005). "Polymorphisms within the canine MLPH gene are associated with dilute coat color in dogs". BMC Genetics. 6 (34). doi:10.1186/1471-2156-6-34. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)

[10] Dayna L. Dreger & Sheila M. Schmutz (2010). "A New Mutation in MC1R Explains a Coat Color Phenotype in 2 Old Breeds: Saluki and Afghan Hound". Journal of Heredity. 101 (5): 644–649. doi:10.1093/jhered/esq061. {{cite journal}}: Unknown parameter |month= ignored (help)

[Murphy1-11] Leigh Anne Clark, Alison N. Starr, Kate L. Tsai & Keith E. Murphy (2008). "Genome-wide linkage scan localizes the harlequin locus in the Great Dane to chromosome 9". Gene. 418 (1–2): 49–52. doi:10.1016/j.gene.2008.04.006. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[12] Sophie I. Candille, Christopher B. Kaelin, Bruce M. Cattanach, Bin Yu, Darren A. Thompson, Matthew A. Nix, Julie A. Kerns, Sheila M. Schmutz, Glenn L. Millhauser, Gregory S. Barsh (2007). "A β-Defensin Mutation Causes Black Coat Color in Domestic Dogs". Science. 318 (5855): 1418–1423. doi:10.1126/science.1147880. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[13] Leigh Anne Clark, Jacquelyn M. Wahl, Christine A. Rees & Keith E. Murphy (2006). "Retrotransposon insertion in SILV is responsible for merle patterning of the domestic dog". PNAS. 103 (5): 1376–1381. doi:10.1073/pnas.0506940103. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[Schmutz2-14] Sheila M. Schmutz, Tom G. Berryere & Dayna L. Dreger (2009). "MITF and White Spotting in Dogs: A Population Study". Journal of Heredity. 100 (Suppliment 1): 566–574. doi:10.1093/jhered/esp029. {{cite journal}}: Unknown parameter |month= ignored (help)

[15] Winge, Ojvind (1950). Inheritance in Dogs: With Special Reference to the Hunting Breeds. Catherine Roberts (translator). Ithaca, N.Y.: Comstock Publishing. p. 194.

[16] Little, Clarence Cook (1957). The Inheritance of Coat Color in Dogs. New York: Comstock Publishing. p. 194. ASIN B0007DYSH6.

[17] Karlsson E. K., Baranowska I., Wade C. M., Salmon Hillbertz N. H., Zody M. C., Anderson N., Biagi T. M., Patterson N., Pielberg G. R., Kulbokas E. J. III, Comstock K. E., Keller E. T., Mesirov J. P., von Euler H., Kämpe O., Hedhammar A., Lander E. S., Andersson G., Andersson L., Lindblad-Toh K. (2007). "Efficient mapping of mendelian traits in dogs through genome-wide association". Nature Genetics. 39 (11): 1304–1306. doi:doi:10.1038/ng.2007.10. {{cite journal}}: Check |doi= value (help); Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

[18] Edward J. Cargill1, Thomas R. Famula, Robert D. Schnabel, George M. Strain & Keith E. Murphy (2005). "The color of a Dalmatian's spots: Linkage evidence to support the TYRP1 gene". BMC Veterinary Research. 1 (1). doi:10.1186/1746-6148-1-1. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link) CS1 maint: numeric names: authors list (link) CS1 maint: unflagged free DOI (link)

[19] Sheila M. Schmutz (December 27, 2008). "Coat Color Alleles in Dogs". Retrieved September 12, 2010.

[20] Pamela A. Davol (January 29, 2001). "B/b, E/e, and Beyond: A Detailed Examination of Coat Color Genetics in the Labrador Retriever". Retrieved September 11, 2010.

[21] "Nonallergenic Dog? Not Really" by Denise Grady, New York Times, 5 Feb 1997

[22] Heutelbeck ARR, Schulz T, Bergmann K, Hallier E (2008). "Environmental Exposure to Allergens of Different Dog Breeds and Relevance in Allergological Diagnostics". Journal of Toxicology and Environmental Health, Part A. 71 (11–12): 751–8. doi:10.1080/15287390801985513. PMID 18569573. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)

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@@ Line 77: / Line 77: @@
 M is dominant to m.  Both heterozygosity and homozygosity of the merle gene (i.e. M/m and M/M) are linked to a range of auditory and ophthalmologic abnormalities.<ref>{{cite journal |author= Leigh Anne Clark, Jacquelyn M. Wahl, Christine A. Rees & Keith E. Murphy |title=Retrotransposon insertion in SILV is responsible for merle patterning of the domestic dog |journal=PNAS |volume=103 |issue=5 |pages=1376-1381 |year=2006 |month=January |doi=10.1073/pnas.0506940103 |url=http://wwww.dx.doi.org/10.1073/pnas.0506940103 }}</ref>
-'''S locus'''
+'''S (spotting) locus'''
 The alleles at the S locus (the [[microphthalmia-associated transcription factor]] gene or MITF) determine the degree and distribution of spotting of an animal's coat.<ref name=Schmutz2>{{cite journal |author=Sheila M. Schmutz, Tom G. Berryere & Dayna L. Dreger |title=MITF and White Spotting in Dogs: A Population Study |journal=Journal of Heredity |volume=100 |issue=Suppliment 1 |pages=566-574 |year=2009 |month=June |doi=10.1093/jhered/esp029 |url=http://www.dx.doi.org/10.1093/jhered/esp029 }}</ref>  There is disagreement as to the number of alleles that occur at the S locus, with researchers postulating either two<ref>{{Cite book |last = Winge |first = Ojvind |others = Catherine Roberts (translator) |year = 1950 |title = '''Inheritance in Dogs: With Special Reference to the Hunting Breeds''' |publisher = Comstock Publishing |location = Ithaca, N.Y. |pages = 194 }}</ref> or four<ref>{{Cite book |last = Little |first = Clarence Cook |year = 1957 |title = '''The Inheritance of Coat Color in Dogs''' |publisher = Comstock Publishing |location = New York |ASIN = B0007DYSH6 |pages = 194 }}</ref> alleles.  The four alleles postulated are:
@@ Line 85: / Line 85: @@
 *s<sup>w</sup> = Extreme pie-bald spotting (Extremely large areas of white, almost completely white)
-S is dominant to s.  DNA studies have not yet confirmed the existance of all four alleles, with some research suggesting the existance of at least two alleles (S and s<sup>p</sup>)<ref name=Schmutz2/> and other research suggesting the possible existence of a third allele (s<sup>i</sup>).<ref>{{cite journal |author=Karlsson E. K., Baranowska I., Wade C. M., Salmon Hillbertz N. H., Zody M. C., Anderson N., Biagi T. M., Patterson N., Pielberg G. R., Kulbokas E. J. III, Comstock K. E., Keller E. T., Mesirov J. P., von Euler H., Kämpe O., Hedhammar A., Lander E. S., Andersson G., Andersson L., Lindblad-Toh K. |title=Efficient mapping of mendelian traits in dogs through genome-wide association |journal=Nature Genetics |volume=39 |issue=11 |pages=1304-1306 |year=2007 |month=November |doi=doi:10.1038/ng.2007.10 |url=http://www.dx.doi.org/doi:10.1038/ng.2007.10 }}</ref>  It has been suggested that what appears to be the result of an s<sup>w</sup> allele is in fact the result of plus and minus modifiers acting on one of the other alleles.<ref name=Schmutz2/>
+S is dominant to s.  DNA studies have not yet confirmed the existance of all four alleles, with some research suggesting the existance of at least two alleles (S and s<sup>p</sup>)<ref name=Schmutz2/> and other research suggesting the possible existence of a third allele (s<sup>i</sup>).<ref>{{cite journal |author=Karlsson E. K., Baranowska I., Wade C. M., Salmon Hillbertz N. H., Zody M. C., Anderson N., Biagi T. M., Patterson N., Pielberg G. R., Kulbokas E. J. III, Comstock K. E., Keller E. T., Mesirov J. P., von Euler H., Kämpe O., Hedhammar A., Lander E. S., Andersson G., Andersson L., Lindblad-Toh K. |title=Efficient mapping of mendelian traits in dogs through genome-wide association |journal=Nature Genetics |volume=39 |issue=11 |pages=1304-1306 |year=2007 |month=November |doi=doi:10.1038/ng.2007.10 |url=http://www.dx.doi.org/doi:10.1038/ng.2007.10 }}</ref>  It has been suggested that what appears to be the result of an s<sup>w</sup> allele is in fact the result of plus and minus modifiers acting on one of the other alleles.<ref name=Schmutz2/>  It is thought that the spotting that occurs in [[Dalmatian (dog)|Dalmatians]] is the result of the interaction of three loci (the S locus, the T locus and F locus) giving them a unique spotting pattern not found in any other breed.<ref>{{cite journal |author=Edward J. Cargill1, Thomas R. Famula, Robert D. Schnabel, George M. Strain & Keith E. Murphy |title=The color of a Dalmatian's spots: Linkage evidence to support the TYRP1 gene |journal=BMC Veterinary Research |volume=1 |issue=1 |pages= |year=2005 |month=July |doi=10.1186/1746-6148-1-1 |url=http://www.dx.doi.org/10.1186/1746-6148-1-1 }}</ref>
 == Postulated Loci ==

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