GNPTG and mucopolysaccharidosis: Among 14 families diagnosed with MPS, 6 novel and 6 reported variants were identified, where 11 families carried variants in MPS-associated genes (NAGLU, SGSH, GALNS), two families carried variants in two genes (VWA3B, GNPTG) that were not previously associated with MPS phenotypes, while one family remained genetically undiagnosed.