German shepherd dog colors Added: 31-03-14

There is a whole range of permissible colors for the breed. here are some common ones.
 
Black and Tan (sg);
Black with Tan markings (sgA)
Black and Red (sb);
Black with Red Markings (sbA)
Black and Silver (ssigr)
Black and Grey (sgr)
Black with Silver markings (ssiA)
Black and Tan-Grey (ssg)
Black with Tan-Grey markings (ssgrA)
Bi-color (a true bi-color has black running down the back side of the hock and should have black markings on the toes)
Blacks (s) and
Sable (gew).

Coat color genetics of the German shepherd dog

The coat-color genetics of the German shepherd dog conforms in most cases to the scheme proposed by Little. In the agouti series, the alleles ay, aw and at are present in the order proposed. However, the dominant black allele AS is absent and the black dogs in this breed are due to a recessive agouti black allele, a. In the extension series, there is evidence for the two alleles E and e as proposed by Little but insufficient evidence to confirm or deny the existence of the other alleles Em and ebr. In the albino series, the alleles C and cch are apparently present and behave as originally suggested. Other phaeomelanin modifiers that are present include the lljin int series and possibly polygenic modifiers. Black-and-tan dogs with patches of gray hairs invading the tan areas and some of the black areas are due to a recessive gene at a new locus. White dogs also are due to a single-factor recessive w that produces a white coat while not affecting the eye or skin pigments.

Trait: a feature or characteristic that is inherited.  It is usually represented by a letter. Example- coat length = L

Gene: the specific segment of DNA on a chromosome that codes for a particular trait. Example- gene for coat length is located on chromosome. 12.

Allele: version of the trait/gene.  Each allele is given a version of the letter assigned to a trait. Example- the gene for coat length has two alleles- one for the smooth coat (L), and one for plush coat (l).

Chromosomes:  “packets” of genes.  Dogs have 78 chromosomes, 38 pairs and two sex chromosomes (determine gender).  The paired chromosomes (sometimes called autosomes or homologous) contain the same Think of it in terms of a shoe store. They have 38 different pairs of shoes (chromosomes).  They are all different styles (different chromosome pairs carry different genes), but each pair have the same style (homologous chromosomes have the same genes).  This means you have 2 copies of a gene – one on the right shoe, and one on the left.  As you look closely at your pair of shoes you’ll notice they are not exactly the same – one is a righty, the other a lefty. (you have 2 copies of the gene, but maybe not the same alleles).  One of the shoe/chromosomes you inherited from the sire, the other from the dam.

Genotype- what alleles you have for a particular gene. Remember you have 2 alleles, one from mom, one from dad.  A genotype is written as 2 letters, each letter represents an allele. 

Heterozygous:  has 2 different alleles in the genotype. Ex- Ll

Homozygous: has the same alleles in the genotype Ex- LL or ll

Phenotype: what the dog looks like. Ex- a dog with the genotype ll has the phenotype of a plush coat.

Dominant: an allele that is expressed in the phenotype no matter what other allele you have. Dominant alleles are written as capital letters. Back to our coat length example-  if a dog has the genotype LL or Ll they have a short coat. L is dominant to l, short hair is dominant to long hair.

Recessive: An allele that is only expressed if a dominant allele is NOT present. Recessive alleles are written as lower case letters.  The only genotype a long haired dog can have is ll.  (* Yes, I know there are “smush” coats out there.  There is another gene that modifies coat length aside from “L”).

We all know that you get ½ of your chromosomes from the sire, and half from the dam.  But how can you tell which ones the pups will get? Simple- you can’t. But you can make predictions using a Punnett Square.

Let’s use this sample problem to give you an idea. You breed a heterozygous short haired bitch (let’s say her father was a plush coat so you know she has at least one recessive allele from him) to a plush coated dog. You want to know many plush coated puppies you will get.

Alleles L= smooth coat, l= plush coat

Sire’s genotype- by looking back we remember that he can only be plush coated if he has both recessive alleles, so he must be ll.

Dam’s genotype- as discussed earlier she is heterozygous, so L l. 

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