Homozygous mutations in PJVK and MYO15A genes associated with non-syndromic hearing loss in Moroccan families.

Objectives: Autosomal recessive non-syndromic hearing loss is a heterogeneous disorder and the most prevalent human genetic sensorineural defect. In this study, we investigated the geneticcause of sensorineural hearing loss in Moroccan patients and presented the importance of whole exome sequencing (WES) to identify candidate genes in two Moroccan families with profound deafness.

Methods: After excluding mutations previously reported in Moroccan deaf patients, whole exome sequencing was performed and Sanger sequencing was used to validate mutations in these genes.

Results: Our results disclosed the c.113_114insT (p.Lys41GlufsX8) and c.406C > T (p.Arg130X) homozygous mutations in PJVK and a homozygous c.5203C > T (p.Arg1735Trp) mutation in MYO15A, both genes responsible for non-syndromic recessive hearing loss DFNB59 and DFNB3, respectively.

Conclusion: We identified in Moroccan deaf patients two mutations in PJVK and one mutation in MYO15A described for the first time in association with non-syndromic recessive hearing loss. These results emphasize that whole exome sequencing is a powerful diagnostic strategy to identify pathogenic mutations in heterogeneous disorders with many various causative genes.