BMAL1 and fatty liver disease: Global and tissue specific knock-out or mutation of clock genes (Rev-erbα/β-/-, Cry1/2-/-, Bmal1-/- and ClockΔ19, Bmal1Δhep) promote hepatic steatosis, and alter blood glucose and lipid homeostasis in lean and high fat diet (HFD) fed obese mice24–28.