Flp-mediated excision of the parental Nintm1a(EUCOMM)Hmgu allele resulted in the removal of the lacZ and neomycin selection cassette leaving exon 2 floxed. 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:277726)