This allele from IMPC was generated at Medical Research Council Harwell by injecting CAS9 RNA, 4 guide sequences CCTTAGGTAGGCAAAGACTGATC, CCTTTGGTGAGAGGGACGACAGC, ATCCAGGAAGTGGACTAAAATGG, GGAGTACTCTTGGTGAACAAAGG, and a donor oligo, which resulted in a Exon Deletion.