PTPN11 and Noonan syndrome: Similarly, inhibition of mouse PTPN11 (encoding SHP2, an upstream promotor of MAPK), caused reduced neurogenesis and increased gliogenesis (Zhu et al., 2018; Ke et al., 2007), whereas activation of SHP2 in a mouse model of Noonan syndrome caused increased neurogenesis and decreases astrogenesis (Gauthier et al., 2007).