The insertion of the L1L2_Bact_P cassette created a deletion of size 5397 starting at position 130993187 and ending at position 130998584 of Chromosome 7 (Genome Build GRCm39). This deletion results in the removal of functionally critical exon(s). The cassette is composed of an FRT site followed by lacZ sequence and a loxP site. This first loxP site is followed by a neomycin resistance gene under the control of the human beta-actin promoter, SV40 polyA, a second FRT site and a second loxP site.