When hepatocytes are damaged or the liver is blocked, serum GGT levels increase.[11] GGTII is an isoenzyme of GGT, and GGT is less specific in PLC diagnosis, while some studies have shown the high specificity of GGTII, with a high positive rate observed in liver cancer, whereas a low positivity observed in the normal population or other diseases.[12] This study revealed that differences in serum GGT activity, AST activity, GGT/ALT ratio, and GGT/AST ratio were observed between the PLC and CHB and the LC groups, which is similar to the results of relevant studies conducted at home and abroad. The gene discussed is GPT; the disease is laryngotracheoesophageal cleft.