Regulation of fetal male germ cell development by members of the TGFβ superfamily

•Nodal, Activin and TGFβ have been implicated in fetal testicular germ cell development•Nodal regulates germ cell pluripotency and differentiation•Activin and TGFβ are involved in germ cell cycle arrest and differentiation•Pathway redundancy has precluded definitive analysis of TGFβ family functions•Understanding germline functions for TGFβ signalling will inform cancer etiology

There is now substantial evidence that members of the transforming growth factor-β (TGFβ family) regulate germ cell development in the mouse fetal testis. Correct development of germ cells during fetal life is critical for establishment of effective spermatogenesis and for avoiding the formation of testicular germ cell cancer in later life. Here we consider the evidence for involvement of various TGFβ family members, attempt to reconcile discrepancies and clarify what we believe to be the likely in vivo roles of these factors.