A – dominant or self black (some geneticists feel that this should be removed to its own Locus – it is not present in the GSD
ay – Tan or Gold Sable (can be ay-ay; ay-aw; ay-as; ay-at; ay-a)
aw – Grey or silver sable (aw-aw; aw-as; aw-at; aw-a) (this is often called wolf color, and may have banding within it)
as – Saddle marked (as-as; as-at; as-a)
at – bi color (at-at; at-a) (color goes further down the legs)
a – No pattern (a-a)
The Black Locus – controls black pigment formation
B – Allows Black pigment to form
b – blocks black pigment in favor of brown, choclate, or liver
Notes on ‘b’ :
-affects both skin and coat simulaneously, and also may be linked to eye color because livers have lighter eyes.
-early views that liver may be lethal were discarded as improbable, and there is no real evidence that it is biologically harmful (Willis, pp39)
The Color Locus – controls pigment in the fur
C – wild type (no change, and no dilution)
cch – Chinchilla affect – partial albinism ‘washy’ coat color (dilutes tan to a yellowish cream or white)
cd – pure white coat with black skin pigment in nose, eye and pad leather.ce – cream colored coats, extreme dilution (from chromadane)
cb – carnaz coats and blue eyes (from chromadane)
ca – true albino (interuption of tyrosene pathway) (from chromadane)
Notes on cch/cd/ca :
-for ca there is still a fair amount of research being done-in Willis’ book he states that cd is an iffy in the GSD
– many believe that homozygous cch is the cause of the white coat in the GSD
- the long held belief that white is degenerative or linked to biological problems is w/o foundation (Willis, pp39)
-seriously defective hips are not a feature of or pecuiliar to whites (Willis pp39) -on this I think he mentioned that whites have a smaller gene pool because they are homo-r, however, with careful breeding and testing they are not any more prone to hereditary disease than are any other GSD (the swiss have demonstrated this with their superior breeding of the BBS)
-whites were generally chosen against in the past because it made it difficult to herd the white sheep and to blend into the dark when guarding. However, Willis states that the White GSD could be very useful as guide dogs if trained properly and he also mentions that they have no diminished desire to herd.. I feel they would almost be more useful during SAR missions because they would be easier to see.
-while white dogs are controverisial with some breeders because the white color is correlated with skin, eye and ear defects. A few studdies have failed to demonstrate that relationship, but even so, white dogs in these breeds remain unpopular (Ruvinski and Sampson, pp82)
The Dilution Locus – dilutes black pigment
D – causes dense black pigment (also known as the wild type)
d – dilutes black to blue or silver
Notes on blue dogs :
-like liver the blue affects the skin and coat simultaneously, as well as having lighter eyes-blues used to be shown in confirmation until a blue won a championship, at which point they were disqualified (willis, pp40)-BBdd looks almost like a black dog dipped in flour
– the blue causes a dusty sheen and can be mistaken as a sable
-the blue color may disapear with age though usually some blue pigment will remain on the muzzle
The Extension Locus - restricts the location of the dark pigment
Em – Black or dark mask
E – dark coat but no black mask except in black dogs
e – clear tan (black usually fades…restricts pigment to red or yellow)
Notes :
-the ‘e’ is more apparent in dogs with tan coloring than in grey sables.
-according to schmutz the e-e may also be something that causes whites or creams.
The Intensity Locus – dilutes tan colors
Int – dilutes tan to ditry white
intm – dilutes tan to light yellowint – no dilution (wild type)
The K Locus – causes self black, originally thought to be part of the Agouti Locus
K = Dominant or self Black
Kbr – sepculative causing of brindle coloring
k – speculative recessive allele, or wild type
Notes :
-this whole locus is considered very new, so there may still be information out on it.
-most GSDs would be k-k; however there have been very rare cases of brindling in GSDs : CH Donna V Allergeiligentor (b. 1924) and her son Igor of Ceara (b. 1927) were both GSDs and brindle, so there may be a few dogs still carrying that allele, though very, very few.
The S Locus – allows for white spotting
S – self colored dogs
si – Irish spotting – 10-30% white (feet, lower legs, belly, chest, tail tip, color and blaze)
sp – Piebald – 20-30%white
sw – extreme white piebald – 10% or less is pigmented
Notes :
-S is incompletley dominant w/ sp
– it causes irish type spotting, (psuedo Irish)…Can produce white like beagles have-S-sw or si-sw makes the dog sp-sp looking.
-I included this Loci because I believe it is what causes Panda spotting in the GSD…I don’t know for sure because there are no recent GSD genetics books that I could find, but it seems like a possibility…It is also in all liklihood fairly rare in the GSD to have the spotting, though clearly exhists as is demonstrated byt the Pandas
The L Locus – controls Coat length
L – short coat
l – long coat
Hope you all enjoy :)
~Cate
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