an inborn error of glycine metabolism, due to a deficiency of glycine dicarboxylase P protein (GCSP), a component of glycine cleavage system; characteristically overwhelming disease in the newborn period, with coma, seizures, and death, or, less often, gradual onset with failure to thrive, focal seizures, and mental retardation; there is massive elevation of plasma glycine, with increased levels in cerebrospinal fluid and urine; plasma hyperosmolality, severe dehydration occur without ketoacidosis; autosomal recessive inheritance; caused by mutation in the GCSP gene on chromosome 9p.
a usually fatal autosomal-recessive aminoacidopathy with accumulation of glycine in body fluids, particularly the blood, urine, and cerebrospinal fluid. It has neonatal onset and is characterized by lethargy, metabolic acidosis with ketosis, absence of cerebral development, seizures, myoclonic jerks, and frequently coma and respiratory failure. It is caused by a defect in one or more of the enzymes involved in the cleavage of glycine. Also called methylmalonicacidemia, propionicacidemia.