ZRSR2 (zinc finger CCCH-type, RNA binding motif and serine/arginine rich 2) is an essential splicing factor involved in the recognition of 3′ splice sites during pre-mRNA splicing. Pre-mRNA splicing is carried out by the major and minor spliceosomes, which target U2- and U12-type introns, respectively. Mutations in ZRSR2 have been associated with various diseases, including X-linked intellectual disability and cancer. The gene is located on the X chromosome and is highly conserved across species.