CLN2 disease previously referred to as late-infantile neuronal ceroid lipofuscinosis (LINCL) (OMIM # 204500) due to its usual presentation, is an autosomal recessive disorder, caused by pathogenic variants in the TPP1 gene on chromosome 11p15 (EC 3.4.14.9). Here, TPP1 is linked to late infantile neuronal ceroid lipofuscinosis.