Familial hemolytic anemia resulting from an abnormal red blood cell pyruvate kinase.

Abstract Hemolytic anemia was identified in a family in which the anemia was associated with a pyruvate kinase which displayed an elevated apparent Michaelis constant for its substrate, phosphoenolpyruvate. Anemia occurred in certain subjects apparently heterozygous for the abnormal gene, but not in others. Presumably, the defect results from a structural alteration of the enzyme.