The screened GYS1, PYGL and PHKG1 genes play crucial roles in the glycogenolysis step of the glucagon signaling pathway, and their overexpression destabilizes glycogenolysis and predisposes one to glycogen storage disease [42,43], which can lead to cirrhosis and liver fibrosis [44]. Here, GCG is linked to Glycogen storage disease due to glycogenin deficiency.