Growth differentiation factors (GDFs) are members of the transforming growth factor (TGF) superfamily that is involved in embryonic development and adult tissue homeostasis. GDF1 was initially identified as a temporally expressed gene in the mouse central nervous system during embryonic development, with only one isoform detected in adult tissues. GDF1 is required for left-right patterning during development and directly interacts with Nodal, another member of the TGF-beta superfamily. It has been sμggested that GDF1 regulates the activity and signaling range of Nodal throμgh direct interaction.