X-linked hemizygous mutations in AIFM1, which encodes apoptosis-inducible factor (AIF) a binder of free PAR, are causative for Charcot–Marie–Tooth disease type 4 in combination with deafness and cognitive impairment (Hu et al, 2017; Wang et al, 2018a). This evidence concerns the gene AIFM1 and deafness.