The V Locus has two different alleles in it: ‘V’, and ‘v’. ‘V’ is the most dominant and ‘v’ is the most recessive. The V alleles are incompletely dominant plus incomplete penetrance. Incomplete penetrance means that some individuals with the same genotype will show different phenotype (visible traits) than others. Some rabbits which carry v show up with white markings and some do not!

V: Non-Vienna
v: Vienna/BEW

NON-VIENNA
The ‘V’ allele is the Non-Vienna allele. All varieties except BEW gene must have at least one of these alleles. If they have two of these alleles, then they are homozygous (Meaning it is “pure” for that allele, so that it cannot produce anything recessive to it no mater what it is bred to.) for non-Vienna. The following varieties have the Vienna allele:

All varieties except Blue Eyed White (BEW) have the non-Vienna gene.
Non-Venna can carry Vienna.

VIENNA
The ‘v’ allele is the Vienna allele. All BEWs must have two of these allele, and are automatically homozygous for BEW. The following varieties have the Vienna allele:

Blue Eyed White (BEW)

​INCOMPLETE DOMINANCE
Oftentimes non-BEWs that carry the Vienna allele will have white markings, often similar to Dutch markings. This is because the Vienna allele is incompletely recessive to the non-Vienna allele. Sports like this have the genetic code Vv.

Not ALL Vv rabbits will have white markings. Ones with white markings are called ‘Vienna Marked’ (shortened to VM), and ones without but that do carry v are called ‘Vienna Carriers’ (shortened to VC). Because not all show signs of it, it is unwise to breed any lines with Vienna in it unless it is specifically for a blue eyed white program. Unfortunately, the allele can hide for a very long time and pop up to ruin other colors down the line.

PURPLE EYES
Blue eyed whites and Vienna marked who are also shaded (cchlc or cchlch) or chocolate based (bb) may have a purple cast to their eyes! This is because Vienna reduces most but not all of the pigment in the eyes. (Versus ruby eyed white, which removes all of the pigment in the eyes, leaving only the red from the blood vessels. Shaded and chocolate both reduce pigment enough that a ruby glow can shine through the eye color. The combination of reduced pigment from the Vienna plus ruby glow from shaded or chocolate

Vienna marked pattern can vary quite dramatically. It can range from a tiny white spot (usually on the head and/or feet) to mostly white.