USH2A and retinitis pigmentosa 1: Three patients who received a USHII diagnosis harboured a combination of one nonsense and one frameshift mutation (family M), a homozygous CNV (family R) and one CNV and a missense mutation (family P) in USH2A. Remarkably, not all the affected members of the family P fulfilled the diagnostic criteria of USH, since two affected siblings (II:1 and II:7) exhibited a less severe phenotype consisting of non-syndromic RP (Supplementary Fig. S1).