The whole-body loss of clock function (e.g., CLOCK or BMAL1 knockout animals) leads to hyperglycemia, glucose intolerance, and, ultimately, obesity and metabolic syndrome [19], whereas ablation of the liver CLOCK impairs glycogenesis and reduces hepatic glucose production [20], indicating the varying consequences of CLOCK dysfunction are tissue-specific [21]. This evidence concerns the gene BMAL1 and Hyperglycemia.