Agouti (aw)

Agouti is a pattern with banded hair on the dorsal area and lighter markings on the dog’s front and underside. This phenotype is found in many wild animals and is also called wolf gray or wolf sable.

What is Agouti?

Agouti causes hair banding in all dorsal regions of ther body. Agouti face markings include a dark nose bar with banded hairs. Many agoutis have lighter “goggles” around tehir eyes.

The banded coat is caused by alternating between phaeomelanin and eumelanin production during hair growth. Agouti often causes more than two bands in each hair and a dark hair tip.

The agouti pattern includes clear ventral tan markings on the eyebrows, cheeks, lower legs, chest, throat, belly, and under the tail. The placement of tan markings is the same you see in a tan point pattern.

The tan markings can vary in intensity (cream, yellow, red) and show countershading.

Agouti is the wild-type when it comes to base patterns. It is found in gray wolves and all sorts of other wild animals where the banded coat causes a dull gray or brownish appearance.

The ASIP^AG allele (aw)

The A-Locus determines the temporal and spatial distribution of phaeomelanin in a variety of different color patterns.

However, these ASIP gene patterns can only be observed in dogs that are neither dominant black (K^B/-) at the K-Locus nor recessive red (e/e) at the E-Locus.

The traditional testing system can only distinguish between four patterns: A^y>a^w>a^t>a. But this test was unreliable for some breeds and could not explain the whole variety of patterns.

New testing can now detect six different patterns controlled by the A-Locus:

ASIPDY	Ay	Dominant Yellow, Clear Sable
ASIPSY	Ays	Shaded Yellow, Shaded Sable
ASIPAG	aw	Agouti, Wolf Grey
ASIPBS	asa	Black Saddle
ASIPBB	at	Black Back, Tan Point
ASIPa	a	Recessive Black

Agouti (ASIP^AG or aw) is recessive to clear sable (DY) and shaded sable (SY), but dominant over saddle pattern (BS), tan point pattern (BB), or recessive black (a).

Agouti is caused by a particular combination of two regions next to the ASIP gene:

The wild-type variant of the ventral promoter (VP2) produces clear tan markings without any banding on the dog’s muzzle, eyebrows, chest, belly, lower legs, and under the tail.

And the wild-type version of the hair cycle promoter (HCP2) causes dorsal hair banding by alternating between dark and light pigment during hair growth.

This combination of VP2-HCP2 promoters (we call this a haplotype) represents the new agouti allele (AG or aw). Other haplotypes represent other alleles (see the A-Locus for more info).

Phenotype	Allele	VP	HCP
Dominant Yellow	Ay	VP1	HCP1
Shaded Yellow	Ays	VP2	HCP1
Agouti	aw	VP2	HCP2
Black Saddle	asa	VP1	HCP4
Black Back	at	VP2	HCP3,4,5
Recessive Black	a	(VP2)	(HCP3)

Dogs with an aw/- genotype can be carriers for black saddle (aw/asa), tan point (aw/at) or recessive black (aw/a).

But the old testing system will report both aw/asa and aw/at as aw/at since it can’t tell the difference between asa and at. Another problem in genetic testing is incorrectly reporting the wild type (aw) when the test can’t detect any of the other variants. Some dogs that test as aw/- are actually at/-.

Agouti Patterns

Agouti causes some hairs to have alternating bands of eumelanin and phaeomelanin.

Usually, the banded hairs are concentrated along the dorsal region of the torso.

The ventral tan markings show only phaeomelanin without dark banding.

But looking at a dog’s hair is not the only way to tell if a dog is truly agouti.

Agouti gives particular face markings with a bar of banded hairs along the ridge of the nose. In some agouti patterns, we find some spectacles of pale hairs around the eyes.

Compared to sable, agouti usually seems way darker, especially in young dogs and puppies.

But the transition between a heavily shaded sable and a lighter agouti pattern is gradual and in some cases needs closer inspection. Usually, shaded sable produces a widow’s peak that does not extend below the eyes and onto the nose ridge like seen in agouti patterns.

Phaeomelanin Intensity

Phaeomelanin have shades from white to yellow to red.

Keeshonds or Pepper-And-Salt Schnauzers are common examples of agouti with low red intensity.

Agouti & Countershading

Countershading (or Urajiro in Japanese dog breeds) causes the belly, throat, muzzle, and eyebrows to express a paler shade of phaeomelanin than the rest of the coat.

Agouti with countershading can produce a very wolfy look.

In some breeds, these lighter areas have very defined borders and can turn almost white.

Banding Color

Most dogs with agouti patterns have black eumelanin. But depending on the B-Locus (liver) and D-Locus (dilution), the eumelanin bands can actually be either black, blue, brown, or lilac.

Of course, color combinations like blue-based agouti or brown-based agouti, or rare lilac-based agouti might give less contrast depending on the color intensity of the base coat.

Masked Agouti

Dogs with agouti patterns can also express a melanistic mask.

Masks add more eumelanin on a dog’s muzzle and may hide some of the lighter face markings.

Agouti Brindle

A brindle pattern adds eumelanin stripes to all areas with phaeomelanin base color.

Since agouti naturally is already quite dark, the added brindle striping might not be visible at first glance. But it might be very obvious in the non-banded areas on the lower legs or muzzle.

Agouti & White

Patches without any pigment can hide some of the agouti pattern.

Extended white spotting can be caused by traits such as piebald or whitehead.

Agouti & Ticking

White spotting can be ticked or roaned. These traits are expressed as dots or hairs in their expected color at their exact position hadn’t the dog been white.

Ticking is not present at birth and begins to show over time. In an agouti & white dog, all the white spotting which is affected by ticking or roan will show some part of the agouti pattern hidden “under” the white coat.

Agouti Merle

Merle can remove some of the eumelanin from a pattern, phaeomelanin is rarely affected. Classic Merle causes a marbled phenotype with random patches of full pigmentation and areas with a diluted color.

Agouti Merles are not that common, to be honest. Most breeds that meddle with Merle want to produce a loud and crisp pattern. And Merle is simply easiest to spot on a solid dark background.

Agouti Domino

In some dog breeds like the Siberian Husky or Alaskan Malamute, agouti meets domino.

Domino reduces eumelanin production and causes lighter phaeomelanin and light undercoat. Combined with agouti, this gives a pale grayish coat, often with only dark hair tips instead of heavy banding.

Domino tends to remove eumelanin from the face and extremities, typically resulting in light “open face” markings. Agouti dominos often retain only a small cross of banded fur or slightly some darker pigment under the eyes, reminiscent of the original pattern.

Btw, an agouti domino can resemble a shaded sable pattern since both can have a widow’s peak on the forehead and a dark-tipped coat on the back.

Dog Breeds with Agouti

Agouti is very common in dogs; after all, it is the original wild-type base pattern.

Some breeds use their own breed terms for this pattern, e.g. “wild boar” in Dachshunds, “sable” (duh!) in German Shepherd Dogs, or “pepper and salt” in Schnauzers.

• Alaskan Malamute
• Caucasian Shepherd
• Czechoslovakian Wolfdog
• Dachshund (Wirehaired)
• Eurasier
• German Shepherd Dog
• German Spitz
• Giant Schnauzer
• Jämthund
• Keeshond
• Miniature Schnauzer
• Norwegian Elkhound
• Petite Basset Griffon Vendéen
• Pomeranian
• Saarloos Wolfdog
• Schnauzer
• Shar Pei
• Siberian Husky
• Swedish Vallhund
• Tamaskan

Learn More

Links

[1] Bannasch, D.L., Kaelin, C.B., Letko, A. et al. Dog colour patterns explained by modular promoters of ancient canid origin. Nat Ecol Evol 5, 1415–1423 (2021). https://doi.org/10.1038/s41559-021-01524-x

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