To ensure these approaches are relevant to thyroid disease-specific cells, iPSCs made by reprogramming cells taken from multiple patients with the Brain-Thyroid-Lung syndrome and congenital hypothyroidism resulting from NKX2-1 heterozygous mutations have been differentiated in vitro into thyroid progenitors using the protocols discovered in the above mouse ESC models (14). Here, NKX2-1 is linked to congenital hypothyroidism.