Rat Terrier Colors
Rat Terrier Color Genetics
There are numerous different genes that determine coat color & pattern in dogs, and to further complicate matters, most of the genes have several different alleles which more specifically determine color/pattern. I will touch on the basics and list some of the genes & alleles that influence color in rat terriers. Keep in mind that dogs have two of each of the genes in each series--one inherited from their dam & one from their sire. I have gathered photographs to illustrate many of the colors & patterns our wonderful rat terriers come in. The term "tri" refers to a dog with tan points on their face, such as a black tri or blue tri, and "bi" is a dog without tan points such as a black bi or blue bi.
The Agouti or "A" Gene Series:
"A" is dominant black, "ay" is responsible for our tan sable dogs, and "at" is responsible for our tricolor dogs (black tri unless that color is changed by the action of another gene)
"A" is dominant to "ay" & "at" and "ay" is dominant to "at".
Examples:
"at at" black tri
"ay at" tan sable
"ay ay" tan sable
"A at" black bi
"A ay" black bi
The "B" Series:
"B" is dominant and means the dog has the ability to form black pigment.
"b" is recessive. In a double dose "bb" results in our chocolate rat terriers.
Examples:
"atat BB" black tri
"atat Bb" black tri that carries chocolate
"atat bb" chocolate tri
The Albino or "C" Series:
"C" is dominant and allows melanin to be formed (allows the formation of color)
"cch" is responsible for apricot & lemon (usually in combination with "ay" but also with "ee")
There are believed to be several other "c" alleles responsible for varying degrees of albinism.
The Dilution or "D" Series:
"D" is dominant and allows intense pigmentation.
"d" is recessive and in double dose dilutes black pigment to blue. In combination with "bb" the result is our "pearl" color rat terriers.
Examples:
"Aat BB dd" Blue bi
"Aat bb dd" Pearl bi
"atat bb dd" Pearl tri
"Aat Bb Dd" Black bi who carries both the chocolate and blue gene.
The Extension or "E" Series:
This series controls extension & restriction of black pigment. "E" permits black pigment to be formed in the coat whereas recessive "e" (in double dose) restricts black pigment in the coat. "ebr" is responsible for the brindle pattern.
The Spotting or "S" Series:
"S" is responsible for solid colored dogs with no (or tiny amounts) of white.
"si" is the Irish Spotting pattern (where the dog has more color than white and the white is restricted to the face, chest, legs/feet)
"sp" is the Piebald pattern (varying amount/sizes of colored spots on white)
"sw" is extreme white. In double dose this will result in an all white dog or white dog with very little color...maybe just a spot on the eye or ear...if there are plus modifiers present. Plus or minus modifiers determine the appearance...
Example: "spsw" with plus modifiers would be a more spotted piebald looking dog while "spsw" with minus modifiers would be a mostly white dog.
The Ticking or "T" Series:
(Ticking refers to the small flecks/spots of color that may not be present at birth but often develop more & more over the months & years)
"T" is dominant and means the dog will have ticking.
"t" is recessive, so in double dose it would prevent a dog from having ticking.
Many rat terriers have ticking but it can vary from a few "freckles" on their legs to flecks all over their body.
I hope this information is helpful...the study of canine color genetics is an ongoing and ever-evolving process. There are still some gray areas and controversy among experts but I have tried to limit the info here to the theories most commonly accepted by genetecists and long time breeders. I've been studying canine genetics for a few years...reading all I can, learning from others who have been studying for years...but of course there is always more to learn!
***I want to say a huge THANK YOU to the breeders who sent me photos to use as examples. They are:
Tracey Kallas, K2 Rat Terriers, photo #'s 5,6,14,15,29-32,34-36,40,41
Lynette Ray, Raydiant Rat Terriers, photo #'s 13,16,22,33,37-39
Lisa Sands, Southern Sands Rat Terriers, photo #'s 12,24-28,42
Theresa ("T")Baker, RatPiT Kennels, photo #'s 17 & 18(Taken by Ruthie...Tigger & Belle's mom)
Thank you ladies!!! |
Date(s): August 8, 2003. Album by Shawspaws. 1 - 43 of 43 Total. 0 Visits. |
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