UPR has also been documented in skin fibroblasts from patients suffering from ceroid lupofusinosis (CLN) 1, 2, 3, 6 and 8, as well as in cells of patients with GM1 gangliosidosis (suffering from reduced activity of β-galactosidase), Tay Sachs disease (reduced activity of β-hexosaminidase A) and Niemann Pick type C2 (mutations in the NPC2 gene) [17]. The gene discussed is NPC2; the disease is Tay-Sachs disease.