This single nucleotide (G) deletion within exon 2 was shown by flow cytometry to cause a null allele. it was generated by injection of Cas9 and guide sequences GTACATCTCTGTCGGCTATG targeting H2-D1b and ATAATCCGAGATTTGAGCCG targeting H2-K1d into NOD/ShiLtDvs embryos, which resulted in this point deletion and the intragenic deletions of H2-D1em5Dvs.