McArdle's disease associated with homozygosity for the missense mutation Gly204Ser of the myophosphorylase gene in a Spanish patient.

We studied a pateint whose clinical, morphological and biochemical findings were consistent with McArdle's disease. Molecular genetic studies revealed that the patient did not harbor the common Arg49Stop mutation and was homozygous for the Gly204Ser mutation. Until now, no patient having the missense mutation in the two alleles has been documented.