The autosomal recessive mutations of CLN8 gene were related to two abnormal phenotypes: progressive epilepsy and mental retardation (EPMR), also known as Northern epilepsy syndrome [23] and a variant late-infantile neuronal ceroid lipofuscinoses (v-LINCL), characterized by earlier onset, faster progression of the disease with speech delayed, developmental delay and seizures [24, 25]. This evidence concerns the gene CLN8 and late infantile neuronal ceroid lipofuscinosis.