Therefore, based on the description and characterization of ATP1A3 mutations related to AHC, the activity of the Na+/K+-ATPase pump appears to be essential for pathogenicity in AHC.36 As a result, most RDP mutations likely influence protein expression and cell surface expression, but in AHC a change in the pump activity could explain the phenotype. This evidence concerns the gene ATP1A3 and alternating hemiplegia of childhood.