Here, we found that HIFs as transcription factors occurred at the promoters of hormones and their receptors respectively (Supplemental Tables 4, 5); this means that HIFs can bind to the promoters of Sstr2, Sstr 5, Ghrhr, Gnrhr, Trhr, Prlr, Drd1, and Mc4r to regulate their transcription pattern during hypoxic stress, such as sleep apnea of hypoxia, chronic obstructive pulmonary disease (33, 63). The gene discussed is MC4R; the disease is sleep apnea syndrome.