This protein is a transcription factor that negatively regulates other myogenic family proteins. Studies of the mouse homolog, I-mf, show that it interferes with myogenic factor function by masking nuclear localization signals and preventing DNA binding. Knockout mouse studies show defects in the formation of vertebrae and ribs that also involve cartilage formation in these structures.MDFI (MyoD Family Inhibitor) is a Protein Coding gene. GO annotations related to this gene include transcription factor binding. An important paralog of this gene is MDFIC.