Pituitary Hormone Deficiency, Combined or Isolated, 1, also known as pituitary hormone deficiency, combined, 1, is related to pituitary hormone deficiency, combined 1 and pituitary hormone deficiency, combined or isolated, 8. An important gene associated with Pituitary Hormone Deficiency, Combined or Isolated, 1 is POU1F1 (POU Class 1 Homeobox 1). Affiliated tissues include pituitary and thyroid, and related phenotypes are failure to thrive and hypothyroidism