GRHL3 and spina bifida: Similarly, loss of Grhl3 leads to fully penetrant thoracolumbosacral spina bifida, occasional exencephaly, neurocognitive and behavioural disorders, defects in epithelial development of the bladder and intestine and convergence-extension defects9,21–23; although embryos survive to birth, Grhl3−/− embryos die soon after due to rapid trans-epidermal water loss as a consequence of an impaired skin barrier and dehydration following exposure to a terrestrial environment24.