SOX2 and Septo-optic dysplasia: Besides, mice with mutations in Sox2 or Sox3, used as animal models of septo-optic dysplasia, display downregulation of Shh expression (Dattani et al., 1998; Dasen and Rosenfeld, 2001; Rizzoti et al., 2004; Kelberman and Dattani, 2006; Zhao et al., 2012).