Myasthenia gravis (MG) is a rare autoimmune disorder caused by specific antibodies against antigenic determinants of the neuromuscular junction, the main being nicotinic acetylcholine receptor (AChR), less frequently muscle‐specific tyrosine kinase (MuSK) or lipoprotein‐related protein 4 (LRP4) [1, 2]. The gene discussed is MUSK; the disease is myasthenia gravis.