Flp-mediated excision of the parental Cybatm1a(EUCOMM)Wtsi allele resulted in the removal of the promoter-driven neomycin selection cassette and the inserted lacZ reporter sequence, leaving behind the loxP-flanked critical exon(s). Further information on targeting strategies used for this and other KOMP alleles can be found at http://www.knockoutmouse.org/aboutkompstrategies. (J:204739)