Within these types, CMT type 2F (CMT2F) and distal hereditary motor neuropathy 2B (dHMN2B) are caused by heat shock 27 kDa protein 1 (HSPB1, also known as HSP27) mutation in chromosome 7q11.23 .
Clinically, [HSPB1.sup.P182L] is causative of dHMN2B, whereas [HSPB1.sup.S135F] is causative of both CMT2F and dHMN2B .
Moreover, HDAC6 inhibitors reverse axonal transport deficits in mouse models of CMT2F  and cellular models of Parkinson's disease  and Huntington's disease  by increasing acetylated [alpha]-tubulin.
Patient-specific iPSCs were generated from one CMT2F patient (female/52-year-old, Korean) with 404C>T (S135F) mutation and one dHMN2B patient (female/8-year-old, Korean) with 545C>T (P182L) mutation of the HSPB1 gene.
In terms of axonal transport, HDAC6 inhibitors reverse CMT2F and dHMN2B-related axonal transport by increasing acetylated [alpha]-tubulin.
In this system, specific cellular models of CMT2F and dHMN2B showed defects in mitochondrial transport, as the absolute velocity of moving mitochondria and the percentage of moving mitochondria were lower than control MNs.
Hence, defects in the axonal trafficking of mitochondria are associated with decreased acetylation of [alpha]-tubulin, which may be the main causative factor for axonopathy in CMT2F and dHMN2B.