The presence of pathogenic variants in the genes EYA1, SIX1, SIX5, PAX3, MITF, SNAI2, SOX10, EDN3, and EDNRB was also investigated in this cohort, but did not detect any potential pathogenic variant in these genes associated with BOR, BO and Waardenburg syndromes. This evidence concerns the gene SIX1 and Waardenburg syndrome.