Pharmacological administration of recombinant FGF21 increases energy expenditure, glucose tolerance, and insulin sensitivity and decreases adiposity, hyperlipidemia, and hepatic triacylglycerol accumulation in rodent and non-human primate models of obesity and type 2 diabetes [12], [13], [14], [15], [16]. The gene discussed is FGF21; the disease is type 2 diabetes mellitus.