Molecular investigation by TGS in the 10 USH patients allowed the identification of 10 different variants in 5 genes, namely MYO7A (n = 6), USH1G (n = 1), PCDH15 (n = 1), CDH23 (n = 1), and USH2A (n = 1), which highlights the genetic and mutational heterogeneity of this syndrome even in a clinically homogeneous group of patients (9 USH1 cases) (Table 2). This evidence concerns the gene PCDH15 and Usher syndrome.