PPT1 and infantile neuronal ceroid lipofuscinosis: Infantile neuronal ceroid lipofuscinosis (INCL), caused by loss of palmitoyl-protein thioesterase 1 (PPT1) on 1p32, shows brain atrophy, neuronal swelling, sudanophilic changes, granular osmiophilic deposits, lysosomal accumulation positive for acidic phophatase in neuronal and astrocytic cells, and rarefaction and shrinking of corticabasal and bulbar neurons [122].