Rr160^tm1Wtg

An enhancer element that lies far downstream of the C-kappa gene segment was targeted by homologous recombination. This "further downstream enhancer element" (Ed) is located 8 kb downstream from another downstream enhancer, the E3' enhancer element (Rr159). The 1.2kb Ed element was flanked by loxP sites with a floxed neomycin selection cassette also being placed immediately downstream. Founder mice were bred with cre transgenic mice to remove the Ed element and the selection cassette. Deletion of the Ed element was confirmed through Southern blotting. (J:134885)