Mutations in CTSD cause congenital, neonatal, late infantile, juvenile, and adult-onset forms of NCL that are collectively referred to as CLN10 disease (Table 1) (Schulz et al., 2013; Mole and Cotman, 2015; Varvagiannis et al., 2018). This evidence concerns the gene CTSD and neuronal ceroid lipofuscinosis.