ATN1 and sialidosis: The most common and best characterized are Unverricht‐Lundborg disease (MYC/ATX‐CSTB), Lafora disease (MYC/ATX‐EMP2A), neuronal ceroid lipofuscinosis (multiple genes), sialidosis (MYC/ATX‐NEU 1), and dentatorubral pallidoluysian atrophy (ATX‐ATN1).99