Abstract: The present invention provides a means for treatment and/or prevention of a disease caused by aberrant splicing, a neurodegenerative disease represented by Alzheimer's disease, or the like. The present invention relates to a nucleic acid which can be associated with generation of a splice variant that lacks exon 5 of presenilin-2 gene, an inhibitor for inhibiting a binding between protein-nucleic acid caused by aberrant splicing, and a method for screening the inhibitor.