Homozygous viable. Nonsense alleles identified by amplicon sequencing. The gk5243 mutation is C->T, flanking sequences TTCAGTCCGACTGTTTTGTGATGGCTGTCT and CAGAACCAATTACGTTTGTCAATTTTCCGC. The gk5244 mutation is C->A, flanking sequences TGTCTGATCCTTTCTCAATAGTTCCATCCT and GCGCTTTTCAGCAATATGATTTTCAGATCC.