There are provided herein transgenic non-human animals and cells comprising a transgene encoding either a mutated human melanocortin type-4 receptor (hMC4R) protein, wherein the mutated protein is misfolded and retained intracellularly, or a wild-type human melanocortin type-4 receptor (hMC4R) protein. Transgenes and targeting constructs used to produce such transgenic animals and cells are also provided, as well as methods for using the transgenic animals in pharmaceutical screening and as commercial research animals for modeling obesity.
