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The human melanocortin-4 receptor plays a critical role regulating energy homeostasis. Studies on obesogenic hMC4R variants have not yet revealed how human melanocortin-4 receptor maintains body weight. Here, we identified a signaling profile for obesogenic constitutively active H76R and L250Q human melanocortin-4 receptor variants transfected in HEK293 cells that included constitutive activity for adenylyl cyclase, cyclic adenosine monophosphate response element-driven transcription, and calcium mobilization, but not phosphorylated extracellular signal-regulated kinase 1/2 activity. Importantly, the signaling profile included impaired α-melanocyte-stimulating-hormone-induced cyclic adenosine monophosphate response element-driven transcription, but not impaired α-melanocyte-stimulating-hormone-induced adenylyl cyclase, calcium, or phosphorylated extracellular signal-regulated kinase 1/2. This profile was not observed for transfected H158R, a constitutively active human melanocortin-4 receptor variant associated with overweight, but not obesity. We concluded that there is potential for α-melanocyte-stimulating-hormone-induced cyclic adenosine monophosphate response element-driven transcription in HEK293 cells transfected with obesogenic human melanocortin-4 receptor variants to be the key predictive tool for determining whether they exhibit loss-of-function. Furthermore, in vivo α-melanocyte-stimulating-hormone-induced human melanocortin-4 receptor cyclic adenosine monophosphate response element-driven transcription may be key for maintaining body weight.