Synthesis and concentration of 5-phosphoribosyl-1-pyrophosphate in erythrocytes from patients with Down's syndrome.

Plasma urate levels and erythrocyte glucose-6-phosphate dehydrogenase activity were not significantly different in patients with Down's syndrome when compared with control subjects with mental retardation. No significant difference was found in 5-phosphoribosyl-1-pyrophosphate (PRPP) concentration and synthesis of PRPP in erythrocytes from glucose between subjects with Down's syndrome and controls. The purine metabolism of Down's syndrome is discussed.