ADIPOQ and obesity due to melanocortin 4 receptor deficiency: The decreased bone mass with obesity may be due to increased marrow adipogenesis at the expense of osteoblastogenesis, and/or increased osteoclastogenesis because of up-regulated production of proinflammatory cytokines, and/or excessive leptin secretion, or reduced adiponectin production, and/or reduced calcium absorption associated with high fat intake.