In the five recessive families, bi-allelic mutations identified in known deafness genes were confirmed by parental genotyping, including p.Q1770X + c.4263delC in OTOF (OMIM 603681) for Family A, c.2406 + 2insT + p.K1409X in OTOF (OMIM 603681) for Family B, c.4961-3C > G + c.4091-1G > A in OTOF (OMIM 603681) for Family C, p.R65H + c.1638delT in TBC1D24 (OMIM 613577) for Family D, and p.A255V + p.R663W in LARS2 (OMIM 604544) for Family E (Table 1). The gene discussed is LARS2; the disease is deafness.