Because hepatic GCK overexpression increases hepatic lipogenesis and plasma levels of triglycerides in rats (O'Doherty et al., 1999), increased hepatic triglyceride production, or steatosis by liver-specific GCK, has been proposed as the likely cause for elevated plasma triglycerides and declining efficiency (Agius, 2014; Meininger et al., 2011). Here, GCK is linked to steatosis.