New research presented at the European Society for Paediatric Endocrinology meeting has found a genetic region that may control testicle development in the fetus. Men have XY sex chromosomes, and the development of testes is thought to occur after upregulation of the testicular SOX9 gene pathway, in the presence of factor SRY on the Y chromosome. However, the mechanism by which this testicular SOX9 upregulation occurs has so far been unclear.
