Phosphoglycerate kinase deficiency: biochemical and molecular genetic studies in a new myopathic variant (PGK Alberta).

Biochemical analysis of muscle in a 37-year-old man with exercise intolerance, myalgia, recurrent myoglobinuria, and retinitis pigmentosa showed phosphoglycerate kinase (PGK) deficiency. Kinetic and physical characteristics of the mutant enzyme differed from those of two previously reported cases, suggesting a distinct mutation. Southern blot analysis showed similar bands in patient and control, but Northern blot analysis of muscle mRNA showed an abnormally large message. These data demonstrate that PGK deficiency is clinically, biochemically, and genetically heterogeneous.