A Locus
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The A Locus, commonly referred to as 'Agouti', controls how and where the eumelanin (B Locus) appears on a dog with kᵇʳkᵇʳ, kᵇʳkʸ, or kyky (K Locus). There are varying degrees of Agouti, starting at Sable, then Agouti, then Tanpoint, and last Recessive Black.
Sable appears on the black, tail, ears, and top of the head and does not appear much further down the legs or face. However Sable has been seen to vary in intensity, although the reasons are unknown as the gene itself remains the same within each variation.
Shaded Sable is seen typically by itself within established breeds rather than with masking or other markings. They are most distinct and appear with the classic Sable "Widow's Peak". Often Shaded Sable can be difficult to distinguish against Grizzle/Domino (E Locus) however the widow's peak is distinct to Sable. Occasionally some dogs may have extremely dark shaded sable, which may actually be carrying Tanpoint which is causing the dark shading and making the dog look as though they have tanpoints rather than sable.
Tipped Sable is much more faded but still seen best within the head, ears, and back area- sometimes on the tail as well. They typically are seen with Masking (E Locus) but can be seen without, usually with the classic widow's peak as well.
Clear Sable is the hardest to distinguish, especially against Recessive Red (E Locus), however the best way to tell is if there are any black hairs on the body. Most commonly Clear Sables are seen with Masking which may make it easier to tell between them and Recessive Red.
Wild Sable, different than the name itself and is often referred to as "Wolf Grey" or "Agouti". The fur on these coats are banded and appear almost "tipped" because of that, rather than the more solid coat of Sable. While similar to Sable, it is known that one way to tell is their "Spectacles" around their eyes. The markings appear darkest on the top of the head, back, and tail tip. When combined with Phaeomelanin Intensity (I Locus), the coat becomes very similar to the tones of grey colored wolves, creating the name Wolf Grey. Sometimes Wild Sable may significantly lighten on the dog, alongside the Phaeomelanin color, as the dog ages.
Something interesting is Border Collies that have the aʷ gene appear as Tanpoints rather than Wild Sable. It is currently still unknown why that is.
Tanpoint appears on the majority of the body, except for the muzzles, chest, legs, and under the tail. The eumelanin present is solid and typically is left with few variations without being modified by another gene. The most well known but often mistaken for a version of sable on adults, is the RALY modifier (RALY) which makes the tanpoints over growing from puppy to adult, recede the black into a sable-like pattern on the back.
Recessive Black is nearly if not completely indistinguishable visually from Dominant Black, without genetic testing. On occasion, Tanpoints with Recessive Black as a recessive may appear to have more muddied tanpoints.
- AʸAʸ, Aʸaʷ, Aʸaᵗ, or Aʸa = Sable
aʷaʷ, aʷaᵗ, or aʷa = Wild Sable
aᵗaᵗ or aᵗa = Tanpoint
aa = Recessive Black
aʸᵗ = Recombinant Fawn (Seems to occur only in some breeds. Appears to look the same as normal Sable or Tanpoint when paired with aᵗ. Unknown placement)
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