White German Shepherd Dog

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The recessive gene for white coat hair was cast in the German Shepherd Dog breed gene pool by the late 19th and early 20th century breeding program that developed and expanded the German Shepherd Dog breed in Germany. It is a historical fact that a white herding dog named Greif was the Grandfather of Horand von Grafrath, the dog acknowledged as the foundation of all contemporary German Shepherd Dog bloodlines. “Der Deutsche Schaferhund In Wort Und Bild" ("The German Shepherd Dog in Words and Picture") written by the recognized father of the breed, Rittmeister (Cavalry Captain) Max von Stephanitz, in 1921 included a photo of a White German Shepherd directly descended from Horand.[1] [2]

Information provided in early books on the German Shepherd Dog, such as "The Alsatian WoIf Dog" written by George Horowitz in 1923 [3], as well as "The German Shepherd, Its History, Development and Genetics" written by M. B. Willis in 1977[4], make mention of Greif and other white German herding dogs, with upright ears and a general body description that resembles modern German Shepherd Dogs, shown in Europe as early as 1882. The early 20th century German Shepherd breeding program extensively line bred and inbred "color coat" dogs that carried Greif's recessive gene for "white coats" to refine and expand the population of early German Shepherd Dogs. From the very these direct ancestors of the German Shepherd Dog forward to the German Shepherds of today, the recessive gene for white colored coats has been carried in the DNA of the breed[5].

White puppies, in some percentage, are born to dark colored German Shepherd parents when both the male and female partners of a mating pair carry the recessive gene for "white coats." The dark coat puppies in such litters will also carry, in some percentage, the recessive white coat gene. When only one partner of a mating pair carries the recessive white coat gene, white puppies will not present in litters, but the dark colored puppies inherit, in some percentage, the recessive white gene. When both the male and female partners of a mating pair have white coats the entire litter of puppies will have white coats.

In 1933 the parent German Shepherd breed club in German rejected white coats as a "defective" breed trait when it elected to adopt an exclusively “wolf-like” breed coloration standard. After WWII German Shepherd breed clubs in countries around the world increasingly adopted the exclusively “wolf-like” coloration breed standard of the parent German breed club. Once adopted, breed club members were required to never intentionally breed dogs that carry the recessive gene for white coats.

Because the German Shepherd dog breed club standard governs the color of German Shepherd dogs that may compete in national kennel club sponsored dog shows, such as the prestigious AKC affiliated Westminster Kennel Club dog show in the United States, white coat German Shepherd dogs were barred from such events in the United States starting in 1959, and other countries of the world through the 1990’s.

During the 1970’s, fanciers of the white coat German Shepherd dog worldwide formed their own White German Shepherd Dog breed clubs to continue to breed dogs that carry the recessive white coat gene to produce white coat puppies. White German Shepherd dog fanciers showed their dogs at small specialty dog shows, but many wanted to show their dogs at the most prestigious national and international dog show events, now open only to “standard color” German Shepherd dog owners.

By the late 1990’s a portion of white coat German Shepherd dog fanciers around the world decided to establish a new White Shepherd breed standard and petition their respective national and international kennel clubs for breed recognition, separate and independent from the German Shepherd dog breed club’s control. To populate the new breed of White Shepherd dogs, breeders around the world continually paired and repaired only white coat German Shepherd Dog sires and dams for several generations to breed what is today considered a "pure" White Shepherd breed.

The Controversy Continues

The white vs colored German Shepherd Dog controversy continues to this day.

Genetics

The genes required to produce white coats with dark eyes, nose, foot pads, etc. occurs in the natual world as is evident in the Arctic Wolf or Canis lupus arctos as well as other subspecies population of Canis lupus.

The domestic dog (Canis lupus familiaris) is a subspecies of the wolf that three modern DNA research teams now believe evolved from just a small population of wolves tamed by humans living in or near China less than 15,000 years ago. The research teams believe the DNA evidence indicates that the original population of domesticated dog then spread out of Asia to the rest of the world with human migration and along trading routes. The research team further concludes that intensive breeding by humans over the last 500 years - not different genetic origins - is responsible for the dramatic differences in appearance among modern dogs.[6]

It is reasonable to conclude that the genetic coding for white coats, present in the wolf genome, was passed into the dog's genome during the era of original domestication.

Coat color has been one of the most often used trait selection criterion for the development of most dog breeds. In a few cases, certain colors were selected against because breeders of the age thought the colors were associated with health problems. Other colors were selected against or for because breeders felt that those colors help that breed do its job better, or more often, coat colors were selected and rejected for simple aesthetic reasons.

There are many misconceptions about white-coat German Shepherd Dogs and the gene that expresses for their coat color. Clarence C. Little's The Inheritance of Coat Color in Dogs hypothesized that dilution or partial albinism ce, ca and cch alleles of the so called (C) gene caused the cream and white coat color variants in domestic dogs. Little's hypothesized partial albinism explanation for cream and white colored coats has been applied across most domestic dog breeds, including white coat dogs from German Shepherd breed lines, since Little first published his book.

However, comparative analysis of the dog genome and specific breed DNA sequences now shows that Little's hypothesized gene (C) color dilution explanation for cream and white colored coats is most likely not a relevant determinant of cream and white coats known to commonly occur in many dog breeds. Little's 1957-era partial albinism dilution explanation, as applied to explain domestic dog white and cream coat colors, can be replaced by the findings of modern genetic research.

Research has shown that a recessive ‘e’ allele at the Extension (E) gene is at least partially responsible for cream and white coat color. The (E) gene, now identified as the Melanocortin-1 Receptor (MC1R) gene, is one of the two genes known to code for alleles that are absolutely fundamental to the formation of all German Shepherd Dog colored coat variations. When the recessive ‘e’ allele is inherited from each breeding pair parent, the e/e genotype offspring of certain breeds, including white coat dogs from German Shepherd breed lines, always have cream or white colored coats [7][8].

White shepherds were once unjustly blamed for color dilution or paling for the entire breed because the recessive 'e' allele of the MC1R (E) gene locus masks expression of alleles at other other gene loci that actually do code for lighter (often termed as diluted or pale) colors of silver, black and tan or liver. German breeders of the 1920's and 1930’s misinterpreted pale-colored offspring of white dogs as an undesirable “white” genetic trait. A colored dog paired with a white GSD always produces full colored puppies because the e allele is recessive.)

References

  1. Stephanitz, V. (1994). The German Shepherd Dog in Word and Picture. Wheat Ridge, CO: Hoflin Pub Ltd. ISBN 9789993280057. 
  2. Strang, Paul (1983). White German Shepherd Book. Medea Pub Co. ISBN 9780911039009. 
  3. Horowitz, George (1927). The Alsation Wolf-Dog: Its origin, history, and working capabilities 2nd ed.. Manchester: Our Dogs Publ. Co.. 
  4. Willis, Malcolm (1977). The German Shepherd Dog, Its History, Development, and Genetics. New York: ARCO Pub. Co. ISBN 9780668040778. 
  5. Rankin, Calumn (2002). The All-White Progenitor: German Sheperd Dogs. Upfront Publishing. ISBN 9781844260225. 
  6. McGourty, Christine (2002-11-22). Origin of dogs traced. BBC News. Retrieved on 2006-11-29.
  7. Schmutz SM, Berryere TG. (July/August 2007). "The Genetics of Cream Coat Color in Dogs". Journal of Heredity. PMID 17485734.
  8. Handley, M. (2007-10-31). The Genetics of Coat Color in the White (German/Swiss) Shepherd Dog. White Shepherd Genetics Project. Retrieved on 2007-11-19.