PPT1 and neuronal ceroid lipofuscinosis: Accordingly, mutations in the gene encoding PPT1, CLN1, cause infantile neuronal ceroid lipofuscinosis (CLN1), a fatal pediatric neurodegenerative disease that presents with sensory loss, motor regression, and seizure (Vesa et al., 1995; Haltia, 2003; Nita et al., 2016).