This allele was generated at The Jackson Laboratory by electroporating Cas9 protein and 2 guide sequences GATTTCAAGTTCACACAACG and GTCTCATGCCTCATCTAGGA, which resulted in a 257 bp deletion beginning at Chromosome 11 position 100,632,662 bp and ending after 100,632,918 bp (GRCm38/mm10). This mutation deletes ENSMUSE00001256338 (exon 4) and 91 bp of flanking intronic sequence including the splice acceptor and donor and is predicted to cause a change of amino acid sequence after residue 89 and early truncation 72 amino acids later.