LRP4 and myasthenia gravis: These include acetylcholine receptor (AChR) [28], muscle-specific kinase (MuSK) [29], lipoprotein receptor-related protein 4 (Lrp4) [30], all associated with myasthenia gravis (MG), and voltage-gated calcium channel (VGCC) associated with PNS Lambert-Eaton myasthenic syndrome (LEMS) [31].