Studies of germline, liver-specific, and adipose-specific deletion of core clock genes indicate that core clocks contribute to liver steatosis mainly through extra-hepatic organs, such as the hypothalamus and adipose (Turek et al., 2005; Paschos et al., 2012; Zhang et al., 2020b), and may be dependent on exposure to circadian insult in early life (Yang et al., 2016). Here, CLOCK is linked to fatty liver disease.