Monday, January 22, 2007
What About That REW Gene?
Need a refresher on the c-series gene before reading this post? No problem. Check out Rabbit Coat Color Gene C.
I have had the very unusual situation that two of the nicest herd bucks I've ever purchased were both tort REW carriers. REW stands for ruby-eyed white. Two REW genes produces a ruby-eyed white rabbit.
I have been asked whether this is a good thing or a bad thing. And, of course, the answer is, "It depends."
Actually, the answer is that it is either a good thing or no thing at all. I can't think of a reason why it would be a bad thing, unless you hate REWs and would consider the REW offspring and descendents in your barn to be automatic culls.
I say that it is nothing because the two REW carriers that I own/owned showed no signs of being REW carriers, which is typical of a full color (C gene) rabbit. One now has over 40 or 45 legs (I've lost track now that I no longer own him) and the other has 11, being shown rarely. Obviously, the c gene didn't hold them back any!
So when is it a good thing? One, in producing properly colored rabbits, and two, in diagnosing confusing colors.
A properly-gened sable point has one sable gene and either a REW or himi gene. I believe there are many seal points out there masquerading as a smutty sable points. Those seal point rabbits would have a genotype of aa B- cchl-cchl D- ee.
Think of it this way, every time you breed two sable points together (or sable point with a blue point), you should get 25% seal points (or blue seal points) on the average. But how many times have you ever heard someone say or list that a rabbit was a seal point?
If you want good sable point color, you have to start with the right genes. That's where your REW carrier comes in handy. If I get a sable point from a tort REW carrier plus any other rabbit, then I know for certain that the rabbit is cchl - c (sable gene/rew gene). Why? Because if the tort/rew-carrier had not given the offspring the REW gene, it would have had to give it the C gene, which would not have allowed the recessive sable gene to express itself.
Certainly there are rufus modifiers that also contribute to a smutty sable point. Good color is never just one simple thing, I'm afraid.
If you want to produce a Siamese sable, then you also have to have a REW or himi gene. Otherwise, you have a seal. It works the same way as the sable point vs. seal point.
I recently got an email from a woman who thought there was an error in a pedigree. The pedigree said that the rabbit was seal. But she felt that it was black. I asked her to check the foot pads and she said they were gray. It certainly sounded black. She said she had listed it as seal because one parent was seal and the other was sable point. She knew that those two rabbits could not produce a black. She's right about that. There's no C gene in that pairing and it is required to produce a black.
So what could be going on? The parent may not have been a seal. How could she test? By breeding a REW to the suspected seal/black. The rew has two c genes, which are recessive to all other c-series genes. If there is one black or blue rabbit in the bunch (or tort or blue tort even), then the rabbit being tested was black. How can I say that with certainty? Because black, blue, tort, and blue tort all require the C gene.
Now if there is a black rabbit, how can I say for certain that it is black and not another confusing seal? The answer is that seal would not be a genetic possibility. It takes two sable genes to make a seal and the REW parent would definitely be contributing a c gene. So anything in this litter that looks black, would be black.
I think that if you are working on colors, REWs are indispensable. And when silver martens become an approved variety of Holland down the road, we will need them to test for the cchd gene - to separate silver martens from sable martens.
So is the REW gene a good thing or a bad thing? I think it is mostly a good thing. Even if you are not working with colors, you may produce some REWs that are highly sellable as utility animals, if nothing else, to those who are working on colors. Plus, it is not impossible to work towards competitive REWs. GC BBF's Coca Cola Bear, a REW, had a successful show career, I do believe. And, he produced the best rabbit that has ever lived in my barn - GC BBF's Yankee Doodle Dandy!
Laurie Stroupe
The Nature Trail Rabbitry “Home Of Grand Champions”
Precious Pet Rabbits
Affordable Web Site Design
¶ 8:59 AM
I have had the very unusual situation that two of the nicest herd bucks I've ever purchased were both tort REW carriers. REW stands for ruby-eyed white. Two REW genes produces a ruby-eyed white rabbit.
I have been asked whether this is a good thing or a bad thing. And, of course, the answer is, "It depends."
Actually, the answer is that it is either a good thing or no thing at all. I can't think of a reason why it would be a bad thing, unless you hate REWs and would consider the REW offspring and descendents in your barn to be automatic culls.
I say that it is nothing because the two REW carriers that I own/owned showed no signs of being REW carriers, which is typical of a full color (C gene) rabbit. One now has over 40 or 45 legs (I've lost track now that I no longer own him) and the other has 11, being shown rarely. Obviously, the c gene didn't hold them back any!
So when is it a good thing? One, in producing properly colored rabbits, and two, in diagnosing confusing colors.
A properly-gened sable point has one sable gene and either a REW or himi gene. I believe there are many seal points out there masquerading as a smutty sable points. Those seal point rabbits would have a genotype of aa B- cchl-cchl D- ee.
Think of it this way, every time you breed two sable points together (or sable point with a blue point), you should get 25% seal points (or blue seal points) on the average. But how many times have you ever heard someone say or list that a rabbit was a seal point?
If you want good sable point color, you have to start with the right genes. That's where your REW carrier comes in handy. If I get a sable point from a tort REW carrier plus any other rabbit, then I know for certain that the rabbit is cchl - c (sable gene/rew gene). Why? Because if the tort/rew-carrier had not given the offspring the REW gene, it would have had to give it the C gene, which would not have allowed the recessive sable gene to express itself.
Certainly there are rufus modifiers that also contribute to a smutty sable point. Good color is never just one simple thing, I'm afraid.
If you want to produce a Siamese sable, then you also have to have a REW or himi gene. Otherwise, you have a seal. It works the same way as the sable point vs. seal point.
I recently got an email from a woman who thought there was an error in a pedigree. The pedigree said that the rabbit was seal. But she felt that it was black. I asked her to check the foot pads and she said they were gray. It certainly sounded black. She said she had listed it as seal because one parent was seal and the other was sable point. She knew that those two rabbits could not produce a black. She's right about that. There's no C gene in that pairing and it is required to produce a black.
So what could be going on? The parent may not have been a seal. How could she test? By breeding a REW to the suspected seal/black. The rew has two c genes, which are recessive to all other c-series genes. If there is one black or blue rabbit in the bunch (or tort or blue tort even), then the rabbit being tested was black. How can I say that with certainty? Because black, blue, tort, and blue tort all require the C gene.
Now if there is a black rabbit, how can I say for certain that it is black and not another confusing seal? The answer is that seal would not be a genetic possibility. It takes two sable genes to make a seal and the REW parent would definitely be contributing a c gene. So anything in this litter that looks black, would be black.
I think that if you are working on colors, REWs are indispensable. And when silver martens become an approved variety of Holland down the road, we will need them to test for the cchd gene - to separate silver martens from sable martens.
So is the REW gene a good thing or a bad thing? I think it is mostly a good thing. Even if you are not working with colors, you may produce some REWs that are highly sellable as utility animals, if nothing else, to those who are working on colors. Plus, it is not impossible to work towards competitive REWs. GC BBF's Coca Cola Bear, a REW, had a successful show career, I do believe. And, he produced the best rabbit that has ever lived in my barn - GC BBF's Yankee Doodle Dandy!
Laurie Stroupe
The Nature Trail Rabbitry “Home Of Grand Champions”
Precious Pet Rabbits
Affordable Web Site Design
¶ 8:59 AM
