Table 1.

The members of the melanocortin receptor family, expression, action, and phenotype of individuals with mutations.

Receptor	Main sites of expression	Physiological functions	Disease phenotype of patients with loss-of-function mutations	OMIM
MC1R	Melanocytes, macrophage	Pigmentation, inflammation	Increased risk of skin cancers	155555
MC2R	Adrenal cortex	Adrenal steroidogenesis	Familial glucocorticoid deficiency	202200
MC3R	Central nervous system (CNS), gastrointestinal (GI) tract, Kidney	Energy homeostasis, inflammation	Obesity	155540
MC4R	CNS, spinal cord	Energy homeostasis, appetite regulation, erectile function	Obesity	155541
MC5R	Lymphocytes, exocrine cells	Exocrine function, regulation of sebaceous glands	Decreased production of sebaceous lipids in mice	600042