The protein encoded by this gene is a member of the fibroblast growth factor (FGF) family. FGF family members possess broad mitogenic and cell survival activities, and are involved in a variety of biological processes, including embryonic development, cell growth, morphogenesis, tissue repair, tumor growth, and invasion. This gene is located in a region on chromosome X, which is associated with Borjeson-Forssman-Lehmann syndrome (BFLS), making it a possible candidate gene for familial cases of the BFLS, and for other syndromal and nonspecific forms of X-linked cognitive disability mapping to this region. Alternative splicing of this gene at the 5' end results in several transcript variants encoding different isoforms with different N-termini.