A glutathione synthetase deficiency that is characterized by massive urinary excretion of 5-oxoproline, metabolic acidosis, hemolytic anemia, and central nervous system damage and that has_material_basis_in homozygous or compound heterozygous mutation in the gene encoding glutathione synthetase (GSS) on chromosome 20q11. The metabolic defect results in decreased levels of cellular glutathione, which overstimulates the synthesis of gamma-glutamylcysteine and its subsequent conversion to 5-oxoproline. [ url:https://pubmed.ncbi.nlm.nih.gov/15990954/ ]