MTM1 and sarcopenia: Importantly,loss-of-function mutations in several MTMR phosphatases (MTM1, MTMR2, andMTMR13) have been identified in genetic conditions, namely X-linked myotubularmyopathy (a muscle degenerative disease that shares some similarities with sarcopenia)and Type-4B Charcot-Marie-Tooth disease (a neurodegenerative condition) [33-36].However, the molecular mechanisms by which the mutations in these phosphatasesinduce such diseases remain largely unknown [19,24].