D-Locus Rabbit Colors

D-locus rabbit colors. Rabbit coat color genetics information pertaining to the 2 D locus rabbit color genes carried by domestic rabbits.

The D-locus is fairly uncomplicated, since there are just two options for rabbit color at the D-locus - dense, and dilute.

‘D’ stands for dense color. ‘D’ is completely dominant.

‘d’ stands for dilute. ‘d’ is completely recessive.

There has been just one mutation at the D-locus. A defect occurred in the production of a protein essential to carrying pigment molecules to their permanent homes as the fetus develops. Therefore, in 'dd' dilute rabbits, only a partial load of pigment is put into place over the body of the little fetus. This results in:

Blue American Rabbit

• An obvious decrease in the intensity of color. Black becomes blue. Chocolate becomes lilac.
  
  
• The dilution occurs in eye coloration as well. Dark brown eyes are diluted to gray-blue. The ruby-casted brown eyes in chocolates become ruby-casted gray-blue eyes.
  
  
• It’s not like dumping a can of white paint into the black paint and ending up with gray paint. The mutation does not change the chemical composition of the pigment itself, only the effectiveness of its transport. The number of molecules that end up actually containing that pigment is reduced, therefore the rabbit’s color ends up looking faded, which is actually quite nice.
  

Self lilac mini rex rabbit, which is a dilute chocolate

• Since the dilute ‘d’ is completely recessive, any dilute rabbit must have received a ‘d’ from each parent, and must carry a genotype of ‘dd.’

• Black and chocolate rabbits carry either DD or Dd at the D-locus.
  
  
• With a double ‘dd,’ the black becomes grayish-blue, known as blue (see blue American rabbit above). The chocolate gene dilutes to a pinkish-dove-gray, known as lilac.
  
  
• Black otters become blue otters.
  

• The rabbits pictured above are Otter Rex Rabbit siblings. The Black Otter is 'D_;' the Blue Otter is 'dd.' This blue otter's genotype can be written in full: at_BBCCddEE
  

Full color black otter; dilute blue otter

• Chestnut agoutis, also called black agoutis (such as castor in Rex) become blue agoutis, also called opals
  
  
• Chocolate agoutis become lilac agoutis (lynx)
  
  
  

Because both black and chocolate can be diluted, there are a total of 4 D-locus rabbit colors....

4 D-Locus rabbit Colors: Black, Chocolate, Blue, Lilac

Every domestic rabbit comes in one of these 4 D-locus rabbit colors, of course modified by its other other pattern (A), color (C), and extension (E) genes.

You can clearly see the gray-blue eyes of this broken blue otter rex rabbit.

Chestnut agouti rabbit, called 'castor' in the Rex breed. Chestnut agoutis carry full density, or 'D_'

Is your Lynx Rabbit a Lilac Agouti
or a Smutty Fawn?

Lynx Netherland Dwarf rabbit.

The term 'lynx' has traditionally been applied to the lilac agouti genotype, especially in the standard Rex breed.

But in some USA breed standards, including the Rex rabbit, both lilac agouti and smutty fawn rabbits are shown as lynx, and the smutty fawn more closely matches the lynx description than does the lilac agouti rabbit.

• A lilac agouti (lynx) is: A_bbC_ddE_
  
  This is an agouti animal with lilac tipping over a rich fawn middle ring. This animal also has a slate blue undercolor, even on the belly as does every agouti animal with full extension (E_) of color. (Note that the Rex standard for 'lynx' disqualifies a slate blue undercolor...oops!)
  
  
• A smutty fawn (bred to match the lynx phenotype) is: A_B_C_ddee + smut modifiers - may be lilac-based, but most likely is blue-based.
  
  This is a blue agouti animal with the double-recessive non-extension 'ee' genes, that wipe out all the blue on an otherwise agouti animal. The non-extension 'ee' also eliminates the slate blue undercolor, leaving just white on the belly (matching the standard). Yet just as in self non-extension torts which have a considerable amount of remaining black smut, smutty blue fawns in the USA have been bred over years to allow modifiers that permit a dusting of blue smut over the entire colored portion of the rabbit.
  
  And yes -- they look almost exactly like a lilac agouti ... until you blow into that belly and find nuthin' but white.
  
  

Right now, the term 'lynx' is really a phenotype description toward which there are two genetic paths (more or less). Breeders are successfully showing both of the above genotypes.

You need to know which of your lynx rabbits is which, so that your breeding program will go in the direction you intend it to go.

To help determine the genotype, take a look at the pedigree. If you see black-based animals such as:

• chestnut agouti (castor)
• opal
• black
• red
• fawn

...your lynx likely has a smutty fawn genotype and a white belly to the skin.

If the pedigree contains chocolate based animals such as:

• chocolate agouti (amber)
• chocolate
• lilac

...your lynx may be a true lilac agouti lynx.

But test-breeding will tell you the real truth about D-locus rabbit colors and which type of lynx you have. If you breed to a chocolate or a chocolate agouti and get NO chocolate-based rabbits, the likelihood dramatically increases that the animal in question is a blue-based smutty fawn.