WT1 and Frasier syndrome: Deletion of many of the genes that regulate SRY expression lead to embryonic or perinatal death in mice (e.g., GATA4, FOG2, or MAP3K4), or are accompanied by additional developmental complications in humans (for example, Frasier syndrome in patients with a mutant WT1 isoform); nonetheless, we detected no developmental defects other than sex reversal or infertility in Gadd45g−/− mice.