MTM1 and X-linked myotubular myopathy: Similar to observations in the Mtm1–/y mice and in patients with XLMTM (38), we noted significantly higher DNM2 protein levels in the TA muscles of Mtm1-KI C375S mice compared with WT mice (2.2-fold), while the Dnm2 mRNA levels remained unchanged (Figure 6, A–C).