In our series, we noticed that both auditory nerve and cochlear dysfunctions were present, as auditory neuropathy was found in five cases: two cases of PMP22 (1.4Mb deletion, point pathogenic variant), one case due to TRPV4 and one case due to ABHD12 (molecular diagnosis was not made for the last one); and endocochlear hearing loss was observed in patients with variants in PRPS1, MPZ, SH3TC2, NEFL and PMP22 (duplication). This evidence concerns the gene PMP22 and auditory neuropathy.