Growth differentiation factor 6 (GDF6) is a member of the bone morphogenetic protein (BMP) family and the TGF-beta superfamily of secreted signaling molecules. It is required for normal formation of some bones and joints in the limbs, skull, and axial skeleton.

Mutations in this gene result in colobomata, which are congenital abnormalities in ocular development, and in Klippel-Feil syndrome (KFS), which is a congenital disorder of spinal segmentation.Required for normal formation of bones and joints in the limbs, skull, and axial skeleton. Play a key role in establishing boundaries between skeletal elements during development (By similarity).Defects in GDF6 are associated with Klippel-Feil syndrome (KFS) .