Through the research findings of Dr. Sheila Schmutz, at the University of Saskatchewan, Canada, we are learning a great deal about what color genes Belgian Shepherd Dog carry. We also must discard long held beliefs and theories about their coat color genetics, as many are no longer accurate.
Using DNA swabs from various Belgian Shepherd Dog ( Groenendaels, Laekenois, Malinois, and Tervuren), submitted from owners in Canada, U.S.A., and Holland, Dr. Schmutz and her team were able to pinpoint coat color genes carried by the individual specimens tested. Some were surprises, some not so much when their progeny were known. We had long been told that the dominant black was the As gene. Through molecular testing this has been disproved. Dominant black is on a separate locus, referred to currently as the “K” locus (for blacK), until that gene is identified. In order of dominance: K = dominant black, kbr = brindle, and k = nonblack.
Uniform black coat in a Groenendael can be inherited as a dominant or as a recessive. Since no living brindle Belgian Shepherds were found to test, we’ll ignore the kbr for now, although historically Belgians have carried this gene. A Groenendael, at the “K” locus, would have any of the following:
KK = two dominant black color genes
Kk = one dominant black and one nonblack color gene
kk = two nonblack color genes.
Uniform black coat in a Groenendael can be inherited as a dominant or as a recessive. Since no living brindle Belgian Shepherds were found to test, we’ll ignore the kbr for now, although historically Belgians have carried this gene. A Groenendael, at the “K” locus, would have any of the following:
KK = two dominant black color genes
Kk = one dominant black and one nonblack color gene
kk = two nonblack color genes
A Groenendael whose genetic makeup is kk, aa would be a recessive black. At the “K” locus, all Tervuren, Malinois, and Laekenois are kk, carrying two nonblack color genes. At the “A” locus they must carry at least one ay allele.
We have, in the last decade or so, seen an increase in Tervuren producing Groenendael puppies. The explanation for this is that besides carrying one ay gene, both parents had to carry the recessive black a gene. The genetic formula for a black puppy from Tervuren parents is the same as a recessive black Groenendael from Groenendael parents, kk, aa.
Only one Groenendael specimen, tested by Dr. Schmutz and her team, carried the at recessive black-and-tan gene, while the rest of the Groenendaels were either ayay or aya. The coat color genetic formula for this single dog was Kk, ayat. Another Groenendael had a genetic formula of KK, ayay. Another was Kk, aya. Yet another was kk, aa. The Malinois and Laekenois tested were kk, ayay, although we know that both can also occasionally carry the at black-and-tan or a recessive black. In summary, at the K locus:
KK – the Belgian is black.
Kk - the Belgian is black but also carries a non-black gene.
kk - the Belgian is not black, or could be a recessive black if carrying the aa recessive black genes at the A locus.
All Laekenois, Malinois, and Tervuren are kk at the K locus. Most are kk, ayay. The litterbox “surprises” come when both parents also carry an at or an a gene instead of another ay. What gene distinguishes a fawn Belgian Shepherd Dog from a lighter colored Belgian? The long-held belief was that it was the C and Cch genes that were responsible. Dr. Schmutz and her team have ruled the Tyrosinase gene out, which is the gene called C in most other mammals. Currently they are conducting molecular testing to finally pinpoint just what gene is responsible.
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