EZH2 and obesity due to melanocortin 4 receptor deficiency: Yet, we cannot rule out the contribution of other epigenetics enzymes (e.g., EZH2, HAT1, LSD2, H3K4me3, H3K9me3, and H3K27me3), previously reported to be elevated in obese-MSCs [16], to alter mitochondrial gene expression and function imposed by obesity.