TMEM161B and holoprosencephaly: While disruption of TMEM161B through bi-allelic missense mutations in humans causes cortical gyration abnormalities, loss of Tmem161b function in mice causes several Shh-related malformations such as holoprosencephaly, eye defects, and craniofacial abnormalities, as well as morphologically abnormal primary cilia in the ventricular zone of the developing cortex 119.