The perturbations observed after the conditional inactivation of β-catenin and the finding that AMH is required for the cytoplasmic accumulation of β-catenin in male MD mesenchymal cells (25) indicate that there is a Wnt/β-catenin pathway required for MD regression which is downstream of the AMH and Wnt7a signaling pathways (121). This evidence concerns the gene AMH and Menkes disease.