Ligand for members of the frizzled family of seven transmembrane receptors. Functions in the canonical Wnt/beta-catenin signaling pathway. Required for normal timing of IHH expression during embryonic bone development, normal chondrocyte maturation and for normal bone mineralization during embryonic bone development. Plays a redundant role in maintaining joint integrity. . This is the function of ENSG00000143816 (WNT9A, Wnt family member 9A).