FAP and obesity due to melanocortin 4 receptor deficiency: Since the normal FAP clearance (as observed during skeletal muscle regeneration from TNFα induced FAP apoptosis) (Lemos et al., 2015) is likely not present under these circumstance, one can speculate that this could lead FAPs to accumulate over time, contributing to increased fatty-degeneration of the skeletal muscles in obesity and T2D.