I'm hoping there are some Sheltie people around who can help me with a query!

I've been interested in doggy genetics for some time, though my focus has mainly been on Dobermanns and Belgian Shepherds, but my friend's little Sheltie has captured my interest and I've been doing research to try to determine her genetic "status" and from where she might have inherited her genes.

She is what appears to be a pure sable - a beautiful light golden colour with white markings - but she has one brown eye and one blue eye. I've spent several hours reading up on Sheltie genetics online and the only conclusion I can come to is that she is a sable-merle. (She does have some hardly recognisable patches of darker fur on some parts of her coat, and half a faded "mask" on one side of her face, if that makes any sense.) This would thus mean that she carried a single dominant merle gene, would it not?

The problem with her carrying a merle gene is that she is from a mating of a sable dog to a tricolour bitch. Her two litter brothers are both shaded sable and have two brown eyes each. Therefore where has her merle gene come from?

If the merle gene is present in her, then one of her parents must have carried it - yet their phenotypes suggest otherwise. I am guessing that the sire must have been a sable-merle because sable-merles are apparently sometimes hard to distinguish from regular sable and whites. Also, I presume that if the dam (a tricolour) had carried a merle gene, she would have had a blue merle phenotype?

Any help with solving this puzzle would be appreciated. :) I am very new to Sheltie colour genetics so I may have missed something.

Sable "maskes" Merle.

A lady i know in Ob had a Sealight /Sable BC (with a Merle Mother)whom she put to a B&W dog. They Had a  Blue merle in the litter & a Shaded Sable dog with Blue eyes & small merley markings around Face & tops of legs.

You have to be VERY careful when putting any Sable dog to a merle

hiya, i have the book genetics for dog breeders and the author roy robinson says the merle gene is dominant,and that in sables carrying the merle gene it is harder to determine by phenotype  than it is with the blue merles which are obvious from their phenotype that they carry the gene.therefore i think youre right she possibly is carrying the merle gene,its just harder to determine just by sight.also if she was carrying it ,it would be a single merle gene(heterozygous) as dogs with a double merle gene(homozygous) present solid white coats,blue eyes and deafness in some degree and often sterility.hope this helps,roy.