The identification of genetic markers for this disease is difficult due to the complex etiology of this disorder and the possible coexistence of other causes of hypopituitarism, such as congenital diseases that lead to an abnormal development of the pituitary gland, as observed in patients who carried the mutations in the PIT1 or PROP1 genes [32,33]. Here, POU1F1 is linked to hypopituitarism.