In order to investigate whether neurons derived from HPRT1 mutant cell lines recapitulated disease phenotypes in vitro, as recently shown in case of patient-specific Lesch-Nyhan Syndrome (LNS) hiPSCs [18], wild-type and mutant cell lines were differentiated into central nervous system (CNS) neurons. Here, HPRT1 is linked to Lesch-Nyhan syndrome.