Genetik II
Meine Eurasier
Schwarze Samojeden
Auf der Spur des a-Allels
Das at-Allel
Pigment type switching
Black Samoyeds
The at-allele in the Eurasier

Black Samoyeds

Sometimes, they still are mentioned – black Samoyeds! Julius Wipfel talked about them in his book „The Eurasier“ and correctly identified the selection for white coat colour as one reason for the loss of many original traits in the breed. From time to time pictures of these non-white dogs still appear on Facebook or forums and one question is raised almost every time: do they still exist? And, if not, would it be possible to get them back by selection within the breed alone? The answer to both questions, of course, is a decisive “no”. In the Eurasier breed, the black coat colour was brought in by the Samoyed Cito vom Pol, all of his direct offspring out of seven litters were black! So, why aren’t there black purebred Samoyeds, anymore?

The actual era of the black Samoyed in Great Britain only lasted for four generations, the last black Samoyed was born even before world war one. Since then, they have disappeared completely and without outcrossing to another breed (or a very unlikely mutation) they’ll never come back.

It started with Sabarka, a dog originating from the area of Archangelsk in European Russia and brought to England in 1889 by Ernest Kilburn-Scott. Sabarka’s coat colour wasn’t white, but solid brown - liver, as we’d call it in the Eurasier - with a few white spots and if you ever paid attention to colour genetics, you’ll know that his basic coat colour, therefore, was black. It’s impossible to determine whether he was a dominant or recessive black dog, both forms seem to be present in the gene pool of present-day Samoyeds. Sabarka was mated to Whitey Petchora; she was genetically white even though you wouldn’t guess from seeing her picture; today her coat colour would probably be called “biscuit”. This mating produced two dogs that were important for the development of the breed – the white Neva and the black Peter the Great. This litter proves that Sabarka was a carrier for white, his genotype at the E-locus was E/e. Whitey Petchora’s genotype was e/e, same as Neva’s. Peter the Great had the genotype E/e (and B/b, but that’s irrelevant here) and he was used for breeding. His son Pedro, too, was black, but as his dam Alaska was white (e/e), he also was heterozygous for white. Two sons and one daughter – Am. Ch. Tamara (pictured on the left) – continued his line to the present day, you’ll find them in the pedigree of every living Samoyed, but unfortunately, all three were white, genotype e/e. As they were bred solely to white dogs, the black coat colour in the Samoyed was therefore extinct in the breed. Pedro did have some black offspring, but I don’t know if they were ever used for breeding. If they were, their lines went extinct quickly.

Beneath its white coat, the Samoyed still has some variation in coat colour left. And so, in hindsight, Cito’s black offspring wasn’t a surprise at all – he was homozygous for dominant black, KB/KB, but for recessive black, too, genotype a/a. All that was needed to bring the black coat colour back to the light was a working Mc1-receptor. Kriskella’s Kiowa of Whiteline produced three black offspring with two different Eurasier dams, one of these has had three litters so far without black puppies, so it’s very unlikely for him to carry the KB-allele, but he does carry the at-allele! Whether the b-allele is still present in the Samoyed is questionable, but there is a slight possibility.

So the explanation for the complete disappearance of all colours but white in the Samoyed breed is actually quite simple – Samoyeds don’t have any working Mc1-receptors left in the breed. Getting rid of a dominant trait is easily done, especially if breeders actively select against this trait.

There’s only one way to get the black Samoyed back – the E-allele has to be reintroduced into the breed, which is only possible by crossbreeding.

One more thing - many Samoyeds have a few black hairs or even patches. These are due to somatic mutations which are not heritable at all (you'd need a mutation in germline cells for that), so breeding Samoyeds with black patches will not bring back black Samoyeds.

Tamara's pedigree:

Heute waren schon 25 Besucher (70 Hits) hier!
News und Updates
18.03.2017 Neue Seite: Fusselmonstereien
Diese Webseite wurde kostenlos mit erstellt. Willst du auch eine eigene Webseite?
Gratis anmelden