myasthenia gravis AChR+ myasthenia gravis https://github.com/monarch-initiative/mondo/issues/10321 MONDO:1060001 Myasthenia gravis characterized by the presence of autoantibodies against the muscle nicotinic acetylcholine receptor (AChR) in the serum, which damage the postsynaptic neuromuscular junction and cause skeletal muscle weakness and fatigue.