[Erythrocyte purine phosphoribosyltransferase activity in girls with the Lesch-Nyhan syndrome].

Purine metabolism was studied and an enzymatic deficiency was detected in 6 girls with Lesh - Nyhan syndrome/LNS/. In erythrocytes of the patients with LNS and of their parents alterations were found in activities of hypoxanthine guanine phosphoribosyl transferase/HGPRT/ and adenine phosphoribosyl transferase/APRT/. A form of LNS was observed, which exhibited a decrease in stability of HGRPT and alteration in sensitivity of the enzyme to inhibitors. Treatment with allopurinol did not affect the HGRPT and APRT activities. Heterogeneity of the Lesh Nyhan syndrome is discussed.