The protein encoded by this gene functions to inhibit WNT proteins, which are extracellular signaling molecules that play a role in embryonic development. This protein contains a WNT inhibitory factor (WIF) domain and five epidermal growth factor (EGF)-like domains, and is thought to be involved in mesoderm segmentation. This gene functions as a tumor suppressor gene, and has been found to be epigenetically silenced in various cancers.