This spontaneous A-to-T transition at chromosome 18 position 45,685,419 (GRCm38) causes a nonsense mutation in the fourth exon changing amino acid 528/793/803 from arginine to a stop codon (NP_536713:p.R528*, ENSMUSP00000067884:p.R793*, NP_001299834:p.R803*). (J:207676, J:222308)