Genetic linkage

I've recently read about linkage on this website; http://www.afrma.org/mk-linkage.htm and I was wondering if this linkage is something to still consider nowadays? Are there still genes linked or have crossovers occurred frequently enough so that it is negligible these days?
I also can't find any other websites explaining linkage about mice specifically, does someone know where I can find them?

Wow- that was an interresting article. Thanks for sharing! the linkage does make a lot if sense when you look at genetics so I would definately say yes. It plays a factor in what you would get.

I think we just refer it this as "dominate to recessive" genes on the same locus.

[Dino] wrote:I've recently read about linkage on this website; http://www.afrma.org/mk-linkage.htm and I was wondering if this linkage is something to still consider nowadays? Are there still genes linked or have crossovers occurred frequently enough so that it is negligible these days?
I also can't find any other websites explaining linkage about mice specifically, does someone know where I can find them?

The P-locus is close to the C-locus. Therefore all combinations of p/p and c-dilutions have been rare because crossovers have been rare. From my experience they are around now and in my breeding programm to breed Argente Cream Tricolors I find many animals, which are p/p ce/ce or p/p ce/cch or even p/p c/cch unfortunately.

Regards, Roland
Chilloutarea Mousery – Tricolor , Splashed , Merle , Recessive Red

Wow I didn't know that it was still something to consider So there are no ways except from crossovers to combine variegated with angora then (because that is on the same chromosome 5)? So the longhared variegated buck I have must be lgh and not go? So you could also not breed a recessive yellow to be lgh (chromosome 8 )?

[Dino] wrote:Wow I didn't know that it was still something to consider So there are no ways except from crossovers to combine variegated with angora then (because that is on the same chromosome 5)? So the longhared variegated buck I have must be lgh and not go? So you could also not breed a recessive yellow to be lgh (chromosome 8 )?

You can breed everything in combination, it is just a question of probability, how quick it will happen.
See, people play Lotto, and it happens that they win.

Very interesting!

Being on the same chromosome doesn't not necessarily mean 2 loci will behave as though they are particularly linked.......if they are far apart on the chromosome they will still behave pretty much as though they are unlinked. Linkage effects vary....the farther apart 2 loci are, the closer to normal mendellic ratios the results will be...the closer together 2 loci are, the less likely the alleles can be combined or uncombined and the farther from mendellic ratios the results will be

ah ok, also very interesting!
There is just no end when you try the learn everything about genetics, I love it!

Ok, I got a real braincracker! I was doing some recalculations on a couple I had made a year ago and I thought I'd take this C and P linkage in account, but it turned out all wrong!
This couple is a pew buck, genetically aa c^h/c pp and a black doe carrying c^h and p (aa C/c^h Pp). So my calculations said that they should either have pews (siam pe and himi pe) and blacks or lilacs (black pe), siamese and himalayan. But I got a black, siamese, himalayan and lilac in one litter.... The linkage suggests that from this couple there can either only be pews and blacks or c-dilutes and lilacs, but that is not the case, because they were all present in the litter.

Then how can this be? Did I make a mistake and were my calculations wrong? Do I have the wrong idea of this genetic linkage between C and P?

You assumed you knew which c's were connected to which p's. If you got siamese out of the group, you know Mom was passing along P-ch (as siamese requires black-eyed and ch). Knowing that Mom's c-p linkage is C-p and P-ch (typical). Dad's is ch-p and c-p (atypical). If you don't know what the linkage is on a particular mouse, assume that they have a dominant gene for one of the two on each chromosome (C-p or c*-P), as that is most common situation.

That said, I just got a litter out of a C/ch p/p doe to a c/c p/* buck and got no black eyes out of 11 (meaning only a 5% chance that he's P/p), so I understand that "uncommon" doesn't mean impossible by any means.  This is how we determine which of our c's and which of our p's is linked.

Yes I didn't think much about wich ones were linked, oops  
Thank you!