Homozygous viable. Nonsense alleles identified by amplicon sequencing. The gk5217 mutation is C->T, flanking sequences GCTGATGCGGACATCCAACTTAGTTAAAAT and CATTCATTTGTGGCTTGACATAAATTATAT. The gk5218 mutation is C->T, flanking sequences GTGATCAGTTCTATTTTTGGTGCAGAACTT and CAGACGAAAAGTCGAATGGCAAGAACTGCT.