Central congenital hypothyroidism in association with combined pituitary hormone deficiencies may be i) syndromic, resulting from mutations in early transcription factors, and associated with developmental abnormalities (eg septo-optic dysplasia and its variants, holoprosencephaly and midline defects, ocular or skeletal defects, and intellectual impairment) or ii) non syndromic resulting from mutations in late transcription factors (PROP1, POU1F1). This evidence concerns the gene PROP1 and central congenital hypothyroidism.