The TGF-β superfamily consists of a large number of structurally related cytokines, including activin/inhibin, the bone morphogenetic proteins (BMPs), the growth and differentiation factors (GDFs), the TGF-βs and a number of proteins involved in developmental patterning. Much of the research into the biology of the TGF-β superfamily has focused on TGF-β 1 (the first to be discovered), and it is this isoform about which most is known. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.