For pathogenic variants in the USH2A gene that can cause both nonsyndromic retinitis pigmentosa and Usher syndrome type IIa (OMIM: 276901), the correlation of missense and truncating variants with the associated phenotypic expression is not always clear, although truncating USH2A variants are more frequently reported in patients diagnosed with a syndromic phenotype [118,119]. This evidence concerns the gene USH2A and retinitis pigmentosa.