Among the 14 patients with identified pathogenic factors (Table 2), 12 had homozygous or compound heterozygous mutations in deafness‐causing genes, including mutations in GJB2 (HL01, HL22), OTOF (603,681; HL02), USH1C (605,242; HL05), MYO15A (602,666; HL06), TBC1D24 (613,577; HL07), OTOA (607,038; HL11), TMC1 (606,706; HL13), EDNRB (131,244; HL15), USH1G (607,696; HL20), TWNK (606,075; HL21), and CDH23 (601,067; HL26), suggesting recessive genetic forms of HL. This evidence concerns the gene TBC1D24 and deafness.