Several studies have found that serum DPP4 levels in patients with NAFLD were related to liver injury markers γ-Glutamyl transpeptidase (GGT), glutamine synthetase (GLUL), and liver histological changes (Tsai et al., 2017; Barchetta et al., 2020), suggesting that liver fat formation and liver damage may be related to the expression of DPP4 in liver tissue. The gene discussed is GLUL; the disease is metabolic dysfunction-associated steatotic liver disease.