Left-right determination factor 2 (Lefty2) aka TGFB4 is a protein that is encoded by the LEFTY2 gene in humans.
Lefty2 is a protein from the TGF-beta cytokine family of proteins and is sometimes referred to as TGFB-4. It is secreted and plays a role in left-right asymmetry determination of organ systems during development. Mutations in this gene have been associated with left-right axis malformations, particularly in the heart and lungs.
Lefty2 is also sometimes referred to as Endometrial Bleeding-Associated Factor (EBAF). Some types of infertility have been associated with dysregulated expression of this gene in the endometrium and the protein may play a role in endometrial bleeding.
Alternative processing of this protein can yield three different products. This gene is closely linked to both a related family member and a related pseudogene.