RYR1 and centronuclear myopathy: Along with the centronuclear myopathies due to BIN1 (where T-tubule abnormalities have already been documented) and dynamin-2 mutation [1], myotubular myopathy likely is an “upstream” defect, resulting in abnormalities in the underlying T-tubule and sarcoplasmic reticular structure upon which RYR1 function is dependent.