While no defined human syndrome has yet been attributed to FOXA2 mutations in OMIM, variants in this gene have been associated with hypopituitarism, hyperinsulinism, craniofacial abnormalities, and midline defects, including a reported case of paramedian cleft lip and palate in a patient carrying a ~5.4 Mb deletion at 20p11.2 encompassing 35 genes, among them FOXA2 [45,46]. Here, FOXA2 is linked to hyperinsulinism.