RecruitingA Natural History Study in Participants With Congenital Myasthenic Syndromes (CMS) Due to Mutations in DOK7, MUSK, AGRN, or LRP4Participants will attend up to 4 study visits to collect clinical assessments. The assessments will evaluate participants' symptoms and quality of life to understand disease activity in patients with CMS due to mutations in DOK7, MUSK, AGRN, or LRP4. More information can be found here: https://clinicaltrials.argenx.com/cms