RYR1 and Myalgia: Gene expression analysis of muscle from patients with a history of statin myalgia who were re-challenged with statins revealed a number of pathways and networks linked with RyR regulatory proteins, including calmodulin and autocrine motility factor (which plays a role in endoplasmic reticulum (ER)/SR-mitochondrial communication) (79), and regulatory Ca2+-binding proteins (calpain, calcineurin) (75).