TPP1 and neuronal ceroid lipofuscinosis: A total of 28 mutations have been investigated in genes (CLN1, CLN2, CLN3, CLN5, CLN6, CLN7, CLN8, CLN10, CLN13, CLN14, and CLCN2) in 28 NCL patients; one mutation was detected in YIF1B gene in one patient who showed symptoms of Kaya-Barakat-Masson syndrome, and one was demonstrated in PLA2G6 gene of one patient who was suspected to have infantile neuroaxonal dystrophy disease.