The L1L2_Bact_P cassette was inserted at position 90516200 of Chromosome 10 upstream of exon 17 (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 a 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 17 at position 90517051. Exon 17 is thus flanked by loxP sites. A null/knockout allele was created by cre recombinase expression in mice carrying the tm1a allele to remove the neo selection cassette and loxP-flanked exon 17. Western blot analysis of cortical tissue lysates from homozygous mice confirmed the absence of protein expression. (J:240601)