Such a model agrees well with recent findings that suggest defective PI 3-phosphate metabolism or recognition, e.g. due to mutations in PTEN, MTMR2, MTMR13, or in the FYVE domain (i.e. a module that binds PI 3-phosphates)-containing protein Frabin/FGD4, as a common feature of neuropathies with myelin overgrowth3,4,14,43. The gene discussed is FGD4; the disease is neuropathy.