Effect of D-Ribose Administration to a Patient with Inherited Deficit of Adenylosuccinase

Adenylosuccinase (EC 4.3.2.2; ASase) deficiency is a newly discovered inborn error of metabolism that involves the purine de novo pathway and results in the accumulation of dephosphorylated substrate derivatives of the defective enzyme, namely succinylaminoimidazole carboxamide (SAICA) riboside and succinyladenosine (S-Ado).1–3 Although substantial progress has been made regarding our knowledge of the inherited disease, including its characterisation at gene level,4–5 much work remains to be done, particularly with respect to the mechanisms whereby the defect exerts its deleterious effects on brain function.