Using custom zinc finger nucleases, exons in the 5' one-third of the gene were targeted. ZFN RNA was microinjected into pronuclei of fertilized B6CBAF1 mouse embryos. This led to the establishment of a line with a biallelic 19 bp deletion (GGGTCTTCAGTCAAAAGAA) in exon 4 in the DENN domain of the encoded peptide. (J:276600)