RYR1 and Charcot-Marie-Tooth disease: Dominant forms of centronuclear myopathy have been associated with mutations in two genes, the dynamin 2 (DNM2) gene on chromosome 19p13.2 [76] also implicated in dominant intermediate (CMTDIB) [80] and axonal (CMT2) [129,130] forms of Charcot-Marie-Tooth disease, and the skeletal muscle ryanodine receptor (RYR1) gene on chromosome 19q13.1 in one isolated case [82].