Haroon hello,

Please, have a look here:

www.ncbi.nlm.nih.gov/pmc/articles/PMC4055921/

www.sciencedirect.com/science/article/pii/S1934590913004566

Hi Haroon,

Your question is worded a little strangely. I am not sure if you are trying to cross 2 cre expressing lines or 2 loxP flanked lines. Assuming you are crossing two cre-driver lines, it is possible, but the number of mice required may become quite substantial depending on your intended outcome. If either of these lines expresses in the testes or ovaries, it will generate a germline mutation for the loxP flanked gene of interest. This will make it impossible to generate wild-type and mutant controls in the same litter.

Hi Haroon, if you write down your breeding crosses very clearly, I will understand what are your intentions. I do not understand yet what exactly you plan to achieve.

Hello Subhash.

I would like to cross B6.Vav1-Cre.MHCII floxed with B6.VE Cadherin-Cre.MHCII floxed to achieve knock out of MHCII on hematopoietic and endothelial cells. I am interested in knowing if genetically it is feasible to perform these kind of breedings!

Hello George, I am trying to cross 2 Cre expressing lines that are floxed (knock out for MHC class II).

To achieve a desired phenotype now I am planning to coss B6.Vav1-Cre.MHCII floxed with B6.VE Cadherin-Cre.MHCII floxed to achieve knock out of MHCII on hematopoietic and endothelial cells simultaneously.

Hi Haroon,

It sounds like you have 3 separate strains:

1) Vav1-Cre

2) Cadherin-Cre

3) Floxed MHCII

Given that Vav1-Cre is expressed in the ovaries and testes, there is no way to generate both wild-type (floxed) and mutant (cre-recombined) offspring with control littermates. The best you can manage is mice germline heterozygous and cell specific deleted for MHCII as controls. It is up to you if that is acceptable.