Any congenital myasthenic syndrome in which the cause of the disease is a mutation in the LRP4 gene. The disease is congenital myasthenic syndrome 17 (MONDO_0014578, a Monarch Disease Ontology id). Also known as: CMS17, LRP4 congenital myasthenic syndrome, congenital myasthenic syndrome caused by mutation in LRP4, congenital myasthenic syndrome type 17, myasthenic syndrome, congenital, type 17.