The battle of the sexes

The sex determining gene, Sry, determines the sex of the organism by initia ting development of a testis rather than an ovary from the cells of the bip otential gonad. In the 10 years since the discovery of Sry, new genes and c ellular pathways that operate in the establishment of the gonadal primordiu m and the initiation of testis development have been discovered. Experiment s defining mechanisms downstream of Sry. are providing clear examples of ho w a regulatory transcription factor initiates cellular processes including proliferation and cell migration, which in turn influence architectural pat terning, fate commitment, and differentiation of cells within an organ. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.