The CYFIP1 gene encodes a protein product that interacts with FMRP, the protein coded by the FMR1 gene causing fragile X syndrome (Entrez Gene: 23191; https://www.genecards.org/cgi-bin/carddisp.pl?gene=CYFIP1&keywords=CYFIP1). This evidence concerns the gene FMR1 and fragile X syndrome.