What role does MC4R play in Haut?

MC4R (melanocortin 4 receptor) is primarily known for its central role in appetite regulation and energy homeostasis. Mutations in MC4R are the most common monogenic cause of early-onset obesity. In skin, MC4R expression is low compared to MC1R, which directly affects pigmentation and inflammation. Some research suggests MC4R may influence sebaceous gland activity and wound healing, but the evidence is weak and mostly mechanistic. Consumer DNA tests that link MC4R variants to skin health often overstate clinical relevance. Without specific SNP data from the provided context, any claim about MC4R and skin remains speculative. The receptor's main action is in the hypothalamus; peripheral effects are not well-established. Therefore, a direct role in acne, aging, or inflammatory skin conditions is not supported by robust human studies. Evidence grade: unclear.