Fig. 2.

The canonical Wnt/β- catenin pathway is active in the embryonic ovaries but not the testes. The gonads from the embryos carrying an Axin2^lacZ allele were stained for β-galactosidase (lacZ) expression. The samples (13.5dpc) are oriented with the anterior end towards the left; the gonad (g) and the mesonephros (a segmentally organized structure that serves as a base for the gonad and a duct system, m) are separated by the dotted line. The downstream target of the canonical β-catenin pathway, Axin2, is expressed in the ovary (B) and not the testis (A).