Modifier genes: where can I find more info?

[user 7388]

Something I've found very elusive in my study of rabbit genetics has been details about the modifier genes.

I've seen them mentioned over and over on many sites, mostly in the form of "there are also modifier genes like rufus, plus/minus (blanket/spot) modifiers, and color intensifiers." And that's all they say!

The rufus modifier seems fairly well explained in a few places, and I believe I understand the concept of the plus/minus or blanket/spot modifiers (adds to or removes patterning on patterned rabbits, which could lead to booted rabbits on broken, or more heavily Vienna marked rabbits, etc) but I can't find any literature about it. As far as colour intensifiers go, the only other one I can find aside from rufus is n, for niger, which can affect how black a black rabbit is.

If anyone has any further reading I can do on these, please share! Or let me know your experiences with modifiers. Are there any more that I'm missing?

Similar to these modifiers for coat, I've heard people call the polygenes that affect gigantism and lopped ears modifiers too. That tracks for me, since neither has a distinct gene (like dw for dwarfism, or M for maned). Have any studies been done on lops and giants, do you have any more information about that you could share? Anything else in the realm of modifiers worth discussing? Perhaps body type, like rabbits being more upright versus compact?

 

[hotzcatz]

After you gather all the information are you going to write a paper on it? Post it online so the rest of us can read it, too? As you've noticed, there is a lot of discussion about a few genes and the rest of them get ignored.

Have you tried looking into the various scientific papers? There's the pet people who keep their buns and are mostly concerned with color genes. Then there's the scientific folks who use rabbits for various lab tests. If you can locate those papers and wade through the scientific languages, they have a lot more in depth information.

This isn't exactly about rabbits, being more about lagomorphs but this sort of paper may be useful to you? https://www.hindawi.com/journals/mi/2015/367670/ I find that site useful when figuring out drugs to use on rabbits since about every single drug has at some point been used on rabbits.

 

[user 7388]

I've now read through several textbooks which were to varying degrees full of information about distinct autosomnal genes, and read through every scholarly article I could keep my eyes uncrossed for about gene mutations, and many many breeder blogs... in the end I could find very, very little useful information, mostly speculation and half-understood ramblings. None of the textbooks even mentioned something like rufus which seems fairly well known in breeder circles. My conclusion for now is that since they aren't distinct genes, the research done on them is lacking, and as polygenes have more to do with selective breeding in general (like breeding giant rabbits) than a genetic breeding program (like breeding true dwarfs.) I've copied the information that seemed pertinent and well understood here: https://www.reddit.com/r/RabbitGenetics/wiki/modifiers

It seems like a lot more about these modifiers, insofar as they relate to rabbits, is known with regards to mice populations. That's probably the better place to look for clarity in scientific literature, for now. There were several books that seemed like they could be promising which I just couldn't find copies of, though, for rabbits; Genetic Studies of the Rabbit by Roy Robinson sounds very promising, and is supposed to be available here: http://lit.rabbitcolors.info/ Unfortunately I couldn't get the plugin to work, and when I tried to download the file directly to open offline it wouldn't open either, so I suspect the file isn't functional anymore on this site.

 

[hotzcatz]

Your Reddit post was interesting, I like the link to the British Rabbit Council's color gene page. I find a verbal description of the rabbit to be much more edifying than a photo since one isn't always sure what to notice in a photo.

Have you tried asking Peter Cheeke? He's a major fund of rabbit knowledge and even answers emails although I don't like to bug him overmuch since he's hopefully writing another rabbit book. He's the author of "Rabbit Production". He may not personally know about the rabbit genetics, but he's probably know who does know? He's a professor emeritus at Oregon State and probably has lots of folks discussing rabbits with him.

 

[user 7388]

Oh, interesting. I haven't reached out directly to anyone, just done some posting on forums and communities like this one when I couldn't find answers just from research. I'll probably wait a bit before reaching out to anyone (I'm still early enough in my researching and self-study that every few weeks I stumble upon a great new resource and learn a tremendous new amount) but when I feel like I've truly hit a wall and have enough expertise otherwise, that might be the necessary next step. Thanks for the idea

 

[hotzcatz]

Actually, bunny breeding is pretty fast, possibly even faster than plants so they're a good group to work with when doing genetic studies. A few years ago, a pair of bunnies from here, Barry & Michelle, went to Punahou, (the high school that 'Barry' Obama went to) so they could study genetics. As angoras, they could study the wool gene as well as the coat color genes. And you have this whole group of online folks here who have and breed bunnies. Perhaps you could do some virtual genetic studies?

The bunnies here are English angora. There is a pair of tortoiseshell siblings, one is 'extra fuzzy' with really thick face furnishings. The other is 'less than normally fuzzy' with less than the usual amount of wool on the face. I have no idea of what genes are involved with that, I would like to find out.

Most of the herd here is descended from three pairs which were imported in 2009. So they're all pretty much linebred by now and are very 'typey'. A pair of does were sent to Maui several years ago in exchange for a Satin doe and her halfbred Satin/German son. They weren't English angora but they were at least angora and not related to the rest of the herd. The doe wasn't a good example of her breed so she was moved on to a different herd and the buck was used for limited breeding just to decrease the amount of inbreeding. That hasn't been a particularly good improvement to the herd so we're phasing out the crossbreds.

However, one of the two does who went to Maui was bred to a buck which came from a FB spinning group. He appears to be English but has no pedigree since he was sold as a 'wooler' without one. Folks who spin yarn will get an angora from a breeder to keep for their fiber and not necessarily for breeding. The bunnies are usually sold without a pedigree and frequently will have some sort of 'fault' so they aren't show stock. The buck imported to Maui may not even be directly from a breeder, he could be an 'ooops' bunny from a spinner who had a pair of 'woolers'. In any case, he's an unpedigreed buck which was bred to one of the two fully pedigreed does who were exchanged for the Satin & her hybrid son.

I have a doe from that breeding, Olivia - who has the normal amount of ear furnishings. She was bred to the fully pedigreed 'sparse ear furnishings' buck, Caesar. From that breeding, we get the two siblings who seem to have the most variance in ear furnishings. DaffyDill, a tort buck, has extra-fluffy face furnishings, although most of it seems to be on his face and not necessarily on his ears but he does have fully fluffy ears. Buttercup, a tort doe, is almost at the opposite extreme of the face furnishings although not quite as sparse as their sire.

This is DaffyDill. He has extra fluffy face furnishings, although it doesn't seem to extend fully up his ears. Although, in that picture perhaps he does have fuzzier ears, they're just not groomed.

What would be the best way to track this gene? Buttercup has been bred to another similar limited pedigree buck from Maui but the babies aren't old enough to see their ear furnishings since they're still too young. DaffyDill has been bred to a fully pedigreed doe from the herd here although she's not due until next month so it will be awhile before we can see if the extra-fuzzy gene will breed true.

Is the face furnishings gene recessive? I'd expect so since it vanishes when a fuzzy faced angora is bred to a clean faced angora. Is the extra fuzzy face gene a separate gene? Is it recessive? How do folks figure this out?

 

[FantatsticFluffle]

Actually, bunny breeding is pretty fast, possibly even faster than plants so they're a good group to work with when doing genetic studies. A few years ago, a pair of bunnies from here, Barry & Michelle, went to Punahou, (the high school that 'Barry' Obama went to) so they could study genetics. As angoras, they could study the wool gene as well as the coat color genes. And you have this whole group of online folks here who have and breed bunnies. Perhaps you could do some virtual genetic studies?

The bunnies here are English angora. There is a pair of tortoiseshell siblings, one is 'extra fuzzy' with really thick face furnishings. The other is 'less than normally fuzzy' with less than the usual amount of wool on the face. I have no idea of what genes are involved with that, I would like to find out.

Most of the herd here is descended from three pairs which were imported in 2009. So they're all pretty much linebred by now and are very 'typey'. A pair of does were sent to Maui several years ago in exchange for a Satin doe and her halfbred Satin/German son. They weren't English angora but they were at least angora and not related to the rest of the herd. The doe wasn't a good example of her breed so she was moved on to a different herd and the buck was used for limited breeding just to decrease the amount of inbreeding. That hasn't been a particularly good improvement to the herd so we're phasing out the crossbreds.

However, one of the two does who went to Maui was bred to a buck which came from a FB spinning group. He appears to be English but has no pedigree since he was sold as a 'wooler' without one. Folks who spin yarn will get an angora from a breeder to keep for their fiber and not necessarily for breeding. The bunnies are usually sold without a pedigree and frequently will have some sort of 'fault' so they aren't show stock. The buck imported to Maui may not even be directly from a breeder, he could be an 'ooops' bunny from a spinner who had a pair of 'woolers'. In any case, he's an unpedigreed buck which was bred to one of the two fully pedigreed does who were exchanged for the Satin & her hybrid son.

I have a doe from that breeding, Olivia - who has the normal amount of ear furnishings. She was bred to the fully pedigreed 'sparse ear furnishings' buck, Caesar. From that breeding, we get the two siblings who seem to have the most variance in ear furnishings. DaffyDill, a tort buck, has extra-fluffy face furnishings, although most of it seems to be on his face and not necessarily on his ears but he does have fully fluffy ears. Buttercup, a tort doe, is almost at the opposite extreme of the face furnishings although not quite as sparse as their sire.

This is DaffyDill. He has extra fluffy face furnishings, although it doesn't seem to extend fully up his ears. Although, in that picture perhaps he does have fuzzier ears, they're just not groomed.

What would be the best way to track this gene? Buttercup has been bred to another similar limited pedigree buck from Maui but the babies aren't old enough to see their ear furnishings since they're still too young. DaffyDill has been bred to a fully pedigreed doe from the herd here although she's not due until next month so it will be awhile before we can see if the extra-fuzzy gene will breed true.

Is the face furnishings gene recessive? I'd expect so since it vanishes when a fuzzy faced angora is bred to a clean faced angora. Is the extra fuzzy face gene a separate gene? Is it recessive? How do folks figure this out?

I don't know about this myself (I only have very fluffy faced angoras), but I found this. I thought it might be helpful. "Some have more or less face furnishings, unrelated to the mane genes or any other known mutation. It may be the case that there are polygene modifiers that affect how much or how little wool an ll angora homozygote will display." from https://www.reddit.com/r/RabbitGenetics/wiki/modifiers/. You can read the whole thing in their post about modifiers.

 

[judymac]

Is the face furnishings gene recessive? I'd expect so since it vanishes when a fuzzy faced angora is bred to a clean faced angora. Is the extra fuzzy face gene a separate gene? Is it recessive? How do folks figure this out?

Rabbitcolors.info has a link to Robinson's book on rabbit genetics. In it, he mentions furnishings (which he coded as Fu), page 297. I have found the plain/furnishings gene to be incompletely dominant. To test this, I mated a plain-faced Satin Angora to a fully furnished English Angora. All of the resulting kits turned out half-way between the two, with a tuft of wool on the forehead, and tufts on the ends of the ears, neither furnished nor plain. However, the amount of furnishings varied considerably. In Robinson's study, mating plain to furnished, he got about 45% plain, 45% with some furnishings, and the rest with a trace of ear tufts.

Years ago, I used a chinchilla buck with great fiber, but lousy furnishings. Decades later, I still get poorly furnished rabbits to occasionally crop up. I'm sure there are polygenes involved as well, that determine the extent of the furnishings.