The targeting vector was designed to insert (from 5' to 3') an internal ribosomal entry site (IRES) fused to an enhanced green fluorescent protein (EGFP) and a self-excising loxP-flanked ACN cassette into exon 11 of the X-linked forkhead box P3 (Foxp3) gene. The ACN cassette contained a neomycin resistance (Neo) gene and a testes-specific angiotensin-converting enzyme promoter-driven Cre recombinase gene (tACE-Cre). The construct was electroporated into C57BL/6-derived Bruce-4 embryonic stem (ES) cells. Correctly targeted ES cells were injected into FVB/N blastocysts and chimeric males were bred to C57BL/6J females. The donating investigator reported that the resulting Foxp3GFP mice were maintained on a C57BL/6J background (see SNP note below). Upon arrival mice at The Jackson Laboratory these mice were bred to C57BL/6J inbred mice (Stock No. 000664) for at least one generation to establish the colony.

A 32 SNP (single nucleotide polymorphism) panel analysis, with 27 markers covering all 19 chromosomes and the X chromosome, as well as 5 markers that distinguish between the C57BL/6J and C57BL/6N substrains, was performed on the rederived living colony at The Jackson Laboratory Repository. While the 27 markers throughout the genome suggested a C57BL/6 genetic background, all 5 markers that determine C57BL/6J from C57BL/6N were found to be segregating. These data suggest the mice sent to The Jackson Laboratory Repository were on a C57BL/6N genetic background.

• 000664 C57BL/6J

Additional Information

• Considerations for Choosing Controls

• Wang Y; Kissenpfennig A; Mingueneau M; Richelme S; Perrin P; Chevrier S; Genton C; Lucas B; DiSanto JP; Acha-Orbea H; Malissen B; Malissen M. 2008. Th2 lymphoproliferative disorder of LatY136F mutant mice unfolds independently of TCR-MHC engagement and is insensitive to the action of Foxp3+ regulatory T cells. J Immunol 180(3):1565-75PubMed: 18209052MGI: J:131351