The genomic structure of mouse Clrn2 (ENSMUST00000053250), and domains of the encoded tetraspan-like glycoprotein (232 amino acids). Black filled boxes represent untranslated region of Clrn2. The positions of the transmembrane (TM) domains (blue) and the structure of Clrn2clarinet (C) and Clrn2del629 (D) alleles are indicated. The clarinet mutation, Clrn2clarinet, (c.12G>A) is predicted to lead to a premature stop codon at position 4 (p.Trp4*) (C), whereas the Clrn2del629 allele consists of a CRISPR/Cas9-mediated 629 nucleotide deletion encompassing exon 2, leading to splicing of exon 1 to exon 3, which if translated would produce a protein lacking 2 (TM2 and TM3) of the 4 transmembrane domains (D). 