A 1.74kB genomic sequence encompassing exon 2 is deleted in mutant mice (g.52662-55846delinsRTLR; GenBank accession no. AB560874). Transcripts show aberrant splicing from exon 1 to 3, generating a frame shift and premature stop codons (p.Asp266AlafsX74 and p.Asp266GlyfsX73).