The nucleic acid sequence of the POMC enhancer is disclosed herein.
Sequences from the human, rat, rabbit, hamster, mouse, and cow POMC
enhancer are disclosed. Hybrid transgenes, comprising a POMC
transcriptional control element operably linked to a nucleic acid
sequence encoding a marker are also enclosed. In addition, transgenic
mice carrying a hybrid transgene including a POMC control element
operably linked to a marker are disclosed herein.