Depletion of Pten in Schwann cells thus leads to an overactivation of the PI3K/Akt/mTOR pathway and focal hypermyelination of axons (Figlia et al, 2017; Goebbels et al, 2012), a phenotype similar to the tomacula in nerves from HNPP patients. This evidence concerns the gene PTEN and hereditary neuropathy with liability to pressure palsies.