Autosomal dominant mutations in ATP1A3 were first shown to cause Rapid-onset Dystonia Parkinsonism (RDP, de Carvalho Aguiar et al., 2004), and later two other neurological syndromes, Alternating Hemiplegia of Childhood (AHC, Heinzen et al., 2012; Rosewich et al., 2012) and CAPOS (cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss, Demos et al., 2014). This evidence concerns the gene ATP1A3 and dystonia 12.