OPA1 and CHARGE syndrome: Although our recruitment focused on probands with nonsyndromic HL, we identified several pathogenic, likely pathogenic and VUS with predicted deleterious effects in genes that can cause nonsyndromic HL or Usher syndrome (CDH23, MYO7A, PCDH15, and USH2A), CHARGE syndrome (CHD7), syndromic optic atrophy (OPA1), and a hereditary sensory and autonomic neuropathy (SPTLC1).