Based on limited published evidence, NBPF19 function remains largely undefined in standard databases. However, noncoding CGG repeat expansions in NBPF19 (also designated NOTCH2NLC) are causative mutations for neuronal intranuclear inclusion disease (NIID) 1. The gene's involvement in NIID pathogenesis appears linked to aberrant repeat expansion rather than conventional protein function. NBPF19 belongs to the NBPF family of genes, though specific biological roles remain undetermined.