Of note, stoichiometry of NF protein subunits (NEFL, NEFM and NEFH) has to be tightly controlled to avoid the formation of NF neuronal cytoplasmic inclusions, axonal degeneration and neuronal death, all pathological hallmarks of motoneuron disorders such as amyotrophic lateral sclerosis (ALS).26 Here, NEFH is linked to amyotrophic lateral sclerosis.