SLC13A5 and obesity due to melanocortin 4 receptor deficiency: Specifically, in comparison to the ubiquitous biosynthesis of mitochondrial citrate and the broad expression of CIC/SLC25A1, SLC13A5 is preferentially expressed in tissues such as the liver, testis, and brain, which would influence physiological and pathophysiological conditions such as lipid metabolism, gluconeogenesis, obesity, type 2 diabetes, and epilepsy in an organ-specific pattern [1,11].