Occasionally Butterflies
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Basic Blue Eyed White Genetics - The Blue Eyed White (BEW) is as it states – a white rabbit with blue eyes. It has nothing to do genetically with the Red Eyed White (REW) as many people would believe. It is a colour in its own right.
The gene that is responsible for the production of the blue eye is called the Vienna gene and it is present in ALL rabbits. The Vienna gene shown in a genotype using the letters VV. A rabbit which is not visually a Blue Eye (and does not have any Vienna breeding behind it) or a carrier of Blue Eye, has two dominant Vienna genes (VV) The gene ONLY comes into play when the recessive gene appears.
The recessive gene is depicted in the genotype with a lower case v - (v). When two recessive genes marry up you will see the resulting baby is a Blue Eyed White (vv). If only one gene is present in the rabbits genetic makeup it will be a carrier (Vv).
The recessive gene is depicted in the genotype with a lower case v - (v). When two recessive genes marry up you will see the resulting baby is a Blue Eyed White (vv). If only one gene is present in the rabbits genetic makeup it will be a carrier (Vv).
Carriers show themselves in different forms. Some have small white patches of fur on their body (mainly on the head or front legs) but some have further white patches on other parts of the body. Some BEW carriers do not show the white marks at all. If a baby is produced in a litter from a BEW to another coloured rabbit – lets say a black – and a coloured baby is born, it will carry the Vienna gene for sure, even if it does not have any visual signs of it.
The carrier of the Vienna gene has had many names over the years and we see different ideas of what it should be called from country to country. I like to call them Vienna Carriers but some people call them Sports, others Vienna Marks. It matters not what they are called, as long as we understand the genetic makeup of the rabbit in question.
Mating two BEW’s together will ensure a FULL litter of BEW’s. The reason for this is the BEW has two recessive genes on the Vienna allele (vv). When (vv) and (vv) are mated together ALL you will be able to produce is (vv) BEW. As has been previously explained there is only room for two genes on the allele and both of them in this case will be recessive.
If you mate a BEW (vv) to a Vienna Carrier (Vv) you will expect in the litter 50% to be BEW and 50% to be carriers.
If you mate two Vienna carriers together (Vv x Vv) you will expect 25% BEW (vv), 25% Normal ((VV)) (not carrying Vienna at all) and 50% Vienna carriers (Vv).
V |
v |
|
V |
V V Non Vienna |
V v Vienna Carrier |
v |
V v Vienna Carrier |
v v Vienna (BEW) |
The Colour of your carriers depends fully on the rest of the genetic makeup of your white rabbit and its partner. Like the albino gene responsible for REW (cc) the Vienna gene masks the other colours of the rabbit, only showing you the white coat and blue eyes. This is called an Epistatic gene.
If you mate a BEW to a Black and you produce Agouti Vienna Carriers AaB-C-D-E-Vv this is because your BEW is really an Agouti in disguise. Because (as has been explained elsewhere in these genetics pages) the Agouti gene (A) is dominant over the blacks self gene (a) ALL the babies born are Agouti Vienna Carriers carrying self.
There are two colour genes you MUST keep out of your BEW breeding program and these are the brown or chocolate gene (carried or expressed) bb - and the light chinchillation gene - cchl Both of these gene cause a glow to the eye when being expressed (visual in the rabbit you are looking at) and both cause the eye in a BEW rabbit to turn purple rather than blue. This is a hugely undesirable point for BEW rabbits and you must not be tempted to use either of these genes when producing or creating carriers.