The L1L2_Bact_P cassette was inserted at a position on Chromosome 11 upstream of exon 2. The cassette is composed of a FRT site followed by a lacZ sequence and a loxP site. This first loxP site is followed by a neomycin resistance (neo) gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site. A third loxP site is inserted downstream of exon 4. Flp-mediated recombination removed the FRT-flanked neo cassette and lacZ reporter. (J:101977)