According to current research, there may be three reasons for the increase in AST/ALT levels associated with NAFLD (1): With the increase in the proportion of fatty tissue in the liver, the burden on normal hepatocytes is aggravated and further destroyed, and a large amount of ALT in the cytoplasm release into the serum, leading to the increase in ALT/AST levels; (2) ALT/AST is related to indocyanine green clearance rate, while indocyanine green clearance rate is related to hepatic blood flow. The gene discussed is GPT; the disease is metabolic dysfunction-associated steatotic liver disease.