Is this just luck or a genetic thing? Two for one!

[TF3]

The smallest kit in our first litter is affectionately know as Half Face.
He has a fabulous personality, but he is just too small for us (he is mostly FG).

He is divided down the midline, with one half being harlequin and the other being plain fawn colour.
There is a little shift of the grey over his bottom and onto the opposite back leg, but I find it fascinating how cleanly he is divided and was wondering if this is just pure luck of placement, or with that midline divide, if it was genetic?
It's like having two different colours in one bunny! :lol:

 

[Susie570]

There are chimera cats, why not chimera rabbits?

I don't think she is though, just an unusual pattern.

 

[TF3]

Yes! That is what I was thinking of! I knew I had seen it on some animal!
No, this isn't that striking, at all!!

 

[Zass]

The mid-line divide is a component of harlequin genetics.

Not all have it, but they cannot be shown without it.

It's controlled by some kind of modifier genes I think..I dunno. :shrug:

 

[akane]

Harlequin in more than just rabbits can cause a split with or without an obvious color change. There are actually tons of split faced patched tabby cats that are not chimera. I had one but she didn't have the clearest split and would have fallen more under a brindle pattern. You can find plenty of them through google and they can't all be chimera. It is not that common. I have a split faced pinto hedgehog out of harlequin parents. He got no markings except half his face is black and half his face is white. Unless you are combining 2 impossible colors to have on the same animal it is quite likely a normal harlequin effect.

 

[TF3]

Doh!
Of course.
Harlequin.
I know what that means (ie the clowns) but didn't connect.
Seriously. I'm a dork

Gosh those are gorgeous kits, Zass!
The half/half mask shows so perfectly.
(not like my muddy little dilute hee hee)

I had a calico cat years ago that had the half black/ half orange face (normal cat, not chimera).

I bet that is an adorable hedgie akane!

 

[Zass]

Gosh those are gorgeous kits, Zass!
The half/half mask shows so perfectly.

They still DQ from having white marks, but it gives me some hope for the line.
I'm really loving this breed.
Both those two turned out to be doelings, and they have quite precious personalities so far.

I aught to at least be able to at least get some decent magpies out of em.

Unfortunately....it's becoming apparent that they are not going to grow like the meat mutts do.

 

[TF3]

At this moment I'd take some slow growth LOL (ok the Hollands are slow!) that is frustrating about the white DQ though!

 

[LPH_NY]

There are chimera cats, why not chimera rabbits?

I don't think she is though, just an unusual pattern.

Is she YOUR cat? She is stunning. I love tortoiseshell and torbie cats. The divide down the face makes her look like two different kitties fused together. That divide, however is common for tortie cats... but the vivid and deeply blue eye on the orange coat is very uncommon! Sorry to derail the thread, lol, but a cat like that deserves some attention!

 

[alforddm]

This has to do with how pigment develops in the body. You see this not only in rabbits and cats but in chimeric and mosaic animals.

This fillies coloring has not been explained completely. She tested not chimeric.

 

[Susie570]

There are chimera cats, why not chimera rabbits?

I don't think she is though, just an unusual pattern.

Is she YOUR cat? She is stunning. I love tortoiseshell and torbie cats. The divide down the face makes her look like two different kitties fused together. That divide, however is common for tortie cats... but the vivid and deeply blue eye on the orange coat is very uncommon! Sorry to derail the thread, lol, but a cat like that deserves some attention!

It is not my cat. There has even been some argument that she is not a true 'chimera', but eh, whatever. Her name is 'Venus' and she has her own facebook page https://www.facebook.com/VenusTheAmazingChimeraCat

There are specific rules for determining a chimera mutation. I believe that one of them is a distinct line of separation for colors that runs down the center of the body. It should even divide the tail. They usually have two different colored eyes. This is very different from the common 'split face' harlequin pattern which is supposed to include ears of opposite colors from the face.

I see that my memory fails me on the chimera distinction. It IS interesting to read about though...

http://en.wikipedia.org/wiki/Chimera_(genetics)

 

[LPH_NY]

The clear dividing line on a tortie cat is not an indication of a chimera. It's fairly common because one color gene must be "turned off" in order to show the other and this happens in clusters as the cells divide in an embryo. The clusters sometimes differ on opposite sides of a dividing line down the face because the cells on the right side of the face are independent of the cells on the left side. On cats, the expression of black and orange coloring is limited to the X chromosome, so black and orange can only exist on the same animal because female (XX) embryos undergo a process which turns off one color/X expression per cell (randomly, but often in clusters). Any male tortie has an extra X chromosome and either could be a chimera OR just an unfortunate recipient of an extra chromosome (and would be sterile).

I'm not saying the pictured cat most definitely IS NOT a chimera... only blood testing would tell for sure. I'm simply explaining how a clear division down the face on a tortie/calico cat can easily happen through the normal course of development of the embryo, and it often does. It's rare for the line to be so perfect and extend all the way down the face, but certainly not impossible. And the eye color suggests an even more improbable genetic mix... but still not clear evidence of chimera. Odd-eyes are not uncommon in cats at all.

In rabbits, the same visual display of black and orange patches is not sex-linked... but I'm guessing there's a similar switching on and off of color expression where black would normally simply override or be hidden by other genes on the entire coat. I don't know much about harlequin genetics, though...