RARRES2 and obesity due to melanocortin 4 receptor deficiency: In addition, high circulating levels of proinflammatory cytokines (e.g., tumor necrosis factor α (TNFα), interleukin-1 (IL-1), and interleukin-6 (IL-6)), markers of lipid metabolism (e.g., fatty acid-binding protein 1 (FABP1)) and adipokines (e.g., leptin, chemerin) have been reported in equine and human obesity (Vozarova et al., 2001; Bozaoglu et al., 2007; Vick et al., 2007; Shi et al., 2012; Qu, Deng & Hu, 2013).