inborn error of brain metabolic pathway inborn error of purine-pyrimidine metabolism pathway X-linked intellectual disability pathway Lesch-Nyhan syndrome pathway 2015-09-02T13:22:28Z An inherited disorder with several psychomotor phenotypes resulting from altered purine metabolism, particularly the salvage pathway, due to defects in the hypoxanthine phosphoribosyltransferase 1 (HPRT1) gene, located on the X chromosome. HG-PRT deficiency pathway PW:0001879 SMP:00364 X-linked hyperuricemia pathway complete hypoxanthine-guanine phosphoribosyltransferase deficiency pathway deficiency of IMP pyrophosphorylase pathway hypoxanthine guanine phosphoribosyltransferase deficiency pathway pathway vpetri