Of note, and in line with the results from genome-wide linkage analysis, filtering of WGS data for rare homozygous variants (see Methods) identified only one such variant, located within one of the two mapped adjacent HBD regions on chromosome 3: g.150660197A > C (c.254–649T > G) in CLRN1. Because the c.254–649T > GCLRN1 affects an intron (between “exon 0b” – an exon contained in transcript NM_001256819.1 – and exon 1) of a proven Usher syndrome gene, and because in silico analysis predicted aberrant splicing (see below), we focused on this alteration. This evidence concerns the gene CLRN1 and Usher syndrome.