We have examined the expression of the transforming growth factor beta 1 gene in a variety of tissues in the developing human embryo. Northern blot analysis revealed the presence of TGF B1 mRNA in the 10-12 week old eye as well as in most first trimester organs with the notable exception of the yolk sack. In an attempt to determine the topographical distribution of TGF B1 transcripts within the eye, we found that messenger RNA levels were higher in the posterior regions of the eye globe.