NHE6 has been implicated in Parkinsonism and deposition of tau neurofibrillary tangles (Garbern et al., 2010; Riess et al., 2013); similarly, emerging evidence links NHE9 with chronic neurodegenerative conditions, including Alzheimer's disease and multiple sclerosis. The gene discussed is SLC9A9; the disease is multiple sclerosis.