A mouse that carried dutch and tri is a very interesting thought. I think I have a couple of those!
*moustress to add to mental checklist of parings she'd like to try*
*yes, she does dream of a realio trulio tricoulor*
The first question is whether the colors shown are black and beige or black and yellow. If it's an actual tricolor, that's absolutely astounding and amazing (and several other early twentieth century pulp zines) and probably wouldn't breed true, much as the other types of genuine tricolours that have appeared. I only call my multi-tone meeces tris as they are not tricolours just meeces with several shades or hues that are based on a single color basis (either eumelanin or phaeomelanin *sp*).i.e. beige, brown, black or cream, yellow, orange, red.
Back to the the subject of marking types and tri (my tri) type meeces. The marking types determine to a great extent where the colors and the divisions of hues appear on the mousie. I think I have worked a way to sort of get a good distribution of a collection of hues on an individual mousie. I am using tri carriers that are marked black. I don't know yet why that works, and even with that, if it were true, the tri thing is stilll very unpredictable. Not the sort of thing a breeder of show meeces really wants to deal with. In addition, there appears to be a sequential process that changes the appearance from generation to generation in mousies that have bold tri markings. Within this sequencing one seems to get sterile individuals, BEW's, and an increased early mortality from unknown causes. I was very pleased when my pairing of the tri buck and b&w marked carrier yielded a large and healthy batch of a dozen babies. Maybe the genome gets played out and needs to go back and pick up some unmanipulated material with work with.
OK, back to the dutch thing; I think that when tris occur that have the colors in patterns that mimic any recognized pattern, dutch, banded, etc., they are broken up within that particular zone, as we see in this girlie. Certain combinations of banding broken into two bold patches across the back seem it indicate sterility, or reproductive difficulties in general. I have Nibbles (shown in other posts) with another tri doe to see if he can git 'er done, and this will be his fourth girlie. None of the first three got pregnant visibly. The two girlies I had with that pattern both died young, one after delivering a dead litter. That probably reveals something really important about the real reason this strain of transgenic meeces were created in the first place. I keep flailing about trying to learn enough about mousie genetics to help me really understand the stuff I read on line. as you can see, I am not at all shy about theorizing and trying to interpret stuff I think I understand. Nor am I shy of asking for help from any source.
I have yet to determine if there's any way to use brindling to achieve a real tricolour. My litters of yellow/tris are intesting, and I am going to make another couple of pairings in both brindling and yellows before I abandon those lines for good.
All I can say for sure about markings types is that without them, one tends to get meeces with all-over mottling, splashing, etc. with little in the way of the islands of pigment that are the most notable feature of of the tri mousies. Over at Funmouse, there is an attempt to define how the transgenic element works; I categorically disagree with 90% of that. There are still two many unanswered questions for standards to be set for tris. Opportunities like this, being asked about the tris, is good for me because it makes me order my thoughts on the matter. It's easy to look at a couple of litters and try to define what you see, but, like I said, I think there is something much more to the whole genotype than The Funmouse or I have yet to discover. The hermaphroditism (I wonder if she has seen that in her mousery) is a weird and wonderful clue that tells me that there is a substantial piece of the tri genome that indicates or mimics the presence of a whole third set of X in the critter.
For what it's worth, the dude who sent me the tris almost three years ago says I'm the only breeder he sent them to who has been able to produce a significant portion of meeces that looks like the tris that he produced in his mousery. I'm just stabbing around in the dark, learning a lot, relearning when I find I'm wrong, and enjoying the results, cuz, hey, they iz all mousies!! And moustress loves da mooziekins, little cutie pot pies that they are.
I do go on, don't I. I think it's because of all that late night time spent awake with thoughts of meeces turning round in my head.