GLI2 and microform holoprosencephaly: GLI2 is a zinc-finger transcription factor involved in the Sonic Hedgehog pathway, and GLI2 variants have been reported in holoprosencephaly (HPE) and/or holoprosencephaly-like (HPEL) phenotypes with pituitary anomalies and postaxial polydactyly (Bertolacini 2012).