PDZD7 and Usher syndrome: As a rare disease with common inherited forms resulting in combined visual and hearing impairment, up to 14 genes, including MYO7A, CDH23, USH1C, PCDH15, USH1G, and CIB2 for USH type I, USH2A, ADGRV1, and WHRN for USH type II, CLRN1 and HARS for USH type III, and PDZD7, CEP250, and C2orf71, are associated with Usher syndrome, with CDH23 mutation identification in this study.