Mitochondrial biogenesis is altered in patient muscle cells. Immunoblot of RC complex, PGC1-α, and TFAM levels in control (C) and patient P2 muscle (Musc) (A), myoblasts (Myb) and myotubes (Myt) (B). α-actinin-2 levels are shown as a loading control for muscle and as an indicator of myogenesis in myotubes. Mitochondrial DNA copy number was determined by qPCR in control (C) and patient (P2) muscle (C) and myoblasts and myotubes (D). Experiments were performed twice, in triplicate each time. Results are expressed relative to a control muscle (C) or myoblast (D) value of 1. Values are the mean ± SD. ns = not significantly different.