mouse genetics

I've been playing a little with breeding mice, can anyone point me to a good mouse genetics site?
I have a black fuzzy/hopper (the intermediate stage I call crawlers) that I just noticed was a different color than the brown littermates.
A tan female started it all, I had her in with a regular old white albino male, held back three of her (brown) babies and started a new colony with them. I was hoping to get a tan one in the f2 litter, but I got all browns, albinos and the black one. I am not sure if it's male or female but I think I will let it live.
IDK if mice genetics work the same as corn snakes but would like to learn a little more Here's a pic of the black one

shed'n my skin said:

I've been playing a little with breeding mice, can anyone point me to a good mouse genetics site?

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The best one I've found is the Finnmouse website (search google, then choose her Genetics/Breeding link, and view the 'old and broken' site) - it talks about all the actual alleles and genes.

I have a black fuzzy/hopper (the intermediate stage I call crawlers) that I just noticed was a different color than the brown littermates.
A tan female started it all, I had her in with a regular old white albino male, held back three of her (brown) babies and started a new colony with them. I was hoping to get a tan one in the f2 litter, but I got all browns, albinos and the black one.

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When you say "tan" do you mean she was all over tan coloured, or do you mean she was the variety that a mouse fancier calls Tan (one colour on the back, tan or light buff on the belly) ?

All-over tan can be a result of several different genes - Red/Fawn is dominant, but is a lethal homozygous - so any animal you see that is red/fawn is heterozygous and will only produce red/fawn offspring 50% of the time. If the original mother had black eyes, she's probably a red.

It can also be the result of the pink-eyed dilution on Self Chocolate (which is a triple recessive - self-coloured hairs are recessive to agouti-banded hairs, chocolate's recessive to black, and pink-eyed is recessive to dark-eyed). This variety is called "Champagne".

And you can also get a tan-coloured mouse if you have the pink-eyed dilution on agouti (dominant agouti, dominant black, recessive pink eyes). This variety is called "Argente" and has a blue-grey coloured undercoat - if you ruffle the fur, the tips of the hair are yellowish, but the undercoat is grey.

The "brown" babies you held back as your F1s are almost certainly Agouti, and will carry the pink-eyed white gene at a minimum. The fact that all the F1 babies were Agouti could make Mum an Argente, but it's equally possible that Dad was hiding an Agouti pattern underneath his white coat. If none of the F1 babies were tan-coloured it's extremely unlikely that Mum was a Fawn or a Red.

The "brown" ones you've got in F2 are probably Agouti (dominant agouti, dominant black, may carry recessives.)

If you got a solid black (AKA "Self Black") F2, that implies that one of the grandparents - either your white male or your female - either was, or carried, the recessive self gene. Do you still have the original female? A good photo of her would go a ways towards working out what she was genetically.

And the white ones could be hiding anything underneath the "Pink-eyed White" masking colouration.

Does that help?

Yes it does thank you! I took a couple pics of the original female 'grandma' The belly is a bit lighter but still tan. Eyes black. I remember there were black mice in the same bin as her when I got her at the pet store, they were all jumbled together in the feeder bin. Male came from someone who had too many feeders, all of them were albinos.
Her litters usually have mostly brown and some white babies. I will have to check out that site!

http://www.geocities.com/mousedomousery/genetics/genetics.html

If you already are familiar with Mendelian genetics, most useful are the "five basic colors" and the "markings" sections. These describe the known loci/alleles.

You must spread some Reputation around before giving it to Serpwidgets again.
Thanks though :wavey:

shed'n my skin said:

Yes it does thank you! I took a couple pics of the original female 'grandma' The belly is a bit lighter but still tan. Eyes black. I remember there were black mice in the same bin as her when I got her at the pet store, they were all jumbled together in the feeder bin. Male came from someone who had too many feeders, all of them were albinos.
Her litters usually have mostly brown and some white babies. I will have to check out that site!

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Mom is a Lethal Dominant Yellow (A^y* AKA "Red"), by the look of her - there are very few genetic combinations where you get black eyes and a yellow/tan coat. In heterozygous form, it makes the yellow coat like you see on her. If you breed two Reds (or a Red and a Fawn, or two Fawns) the homozygous embryos die a couple of weeks before birth and are reabsorbed.

It's quite odd, however, that you've never yet gotten a Red or a Fawn (pink-eyed Red) from her - she should be passing on the gene about half of the time. Unless of course the luck of the draw is making it so that the 'white' babies are actually something like the "old" version of Cream... (heterozygous A^y with either homozygous recessive 'chinchilla' c^ch, homozygous recessive 'extreme dilution' c^e, homozygous recessive himalayan c^h, homozygous recessive c ... or a combination of those alleles, which act together as codominants like Ultra and Amel.)

One would still think that you'd have gotten at least one Red or Fawn baby out of them, since the Lethal Yellow gene is dominant (and you need two copies of the recessive to get the pink-eyed white offspring). Just goes to show the folly of trying to base expectations on statistical probability!

With the probably genotype of your female, however (Dominant Lethal Yellow), you won't get any tan/red/fawn babies out of your F1 offspring - because they don't carry the dominant gene.

Well, a lot of her babies have gotten fed to snakes when they were still pinkys, and I did keep the darker agouti ones to add a little variety to the mouse bunch. So possibly I had some that were light like you describe and became snake food before the eyes opened. Their eyes would have been black and not pink? i guess I could keep another one of her litters and find out. She's a good mom. Thanks again Ssthisto!