The L1L2_Bact_P cassette was inserted at position 169825258 of Chromosome 1 upstream of exon 8 (Build GRCm39). The cassette is composed of an FRT site followed by lacZ sequence and a loxP site. This first loxP site is followed by neomycin resistance 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 8 at position 169826185. A knockout reporter allele was created by cre recombinase expression in mice removing exon 8 and the neomycin selection cassette. Further information on targeting strategies used for this and other IKMC alleles can be found at http://www.informatics.jax.org/mgihome/nomen/IKMC_schematics.shtml. (J:236031)