CLN3 disease, also known as juvenile neuronal ceroid lipofuscinosis (JNCL – Batten disease), is a childhood-onset neurodegenerative disorder resulting from pathogenic variants in CLN3 that lead to the pathological accumulation of ceroid lipofuscin in lysosomes of multiple cell types, with neurons displaying particular vulnerability [1, 2]. Here, CLN3 is linked to juvenile neuronal ceroid lipofuscinosis.