A short-term trial (10 days) with a “read through” compound able to synthesize full proteins from transcripts containing premature termination stop codons (i.e., gentamicin) failed to normalize 31P magnetic resonance spectroscopy indicators of myophosphorylase deficiency in the muscle of McArdle patients (Schroers et al., 2006). This evidence concerns the gene PYGM and hyperinsulinemic hypoglycemia, familial, 4.