Variants in other genes associated with autosomal recessive disease exhibit similar behavior: p.Y201C in ARSB (mucopolysaccharidosis (MPS) VI) [30, 31]; p.G269S in HEXA (Tay–Sachs disease) [32]; p.R229Q in NHPS2 (nephrotic syndrome) [33, 34]; p.C759F in USH2A (found in the homozygous state in retinitis pigmentosa patients, but not Usher syndrome [35]; and p.A138E in TMPRSS3 (non-syndromic hearing loss and deafness) [36]. This evidence concerns the gene HEXA and Usher syndrome.