AIM: To probe the value of γ-glutamyl transpeptidase (GGT)messenger RNA in monitoring canceration of liver cells andfor early diagnosis of hepatocellular carcinoma (HCC), byresearching the types of GGT messenger RNA (GGTmRNA)in liver tissues and peripheral blood of different hepatopathy.METHODS: The three types of GGTmRNA (A, B, C) in livertissues and peripheral blood from the patients with HCC,noncancerous hepatopathy, hepatic benign tumor, secondarycarcinoma of liver, and healthy persons were detected byreverse-transcription polymerase chain reaction (RT-PCR).RESULTS: (1) In normal liver tissues, type A waspredominantly found (100.00 %), type B was not found,type C was found occasionally (25.00 %). (2) The distributionof types of GGTmRNA in liver tissues with acute hepatitis,chronic hepatitis, cirrhosis, alcoholic hepatopathy was similaras in normal liver tissues (P＞0.05), but type B was found in3 of 18 patients with chronic hepatitis (16.67 %), and alsoin 3 of 11 patients with cirrhosis (27.27 %). (3) There wasno significant difference of types of GGTmRNA between livertissues with hepatic benign tumor, secondary carcinoma ofliver and normal liver tissues (P＞0.05). (4) Type B waspredominant in cancerous tissues with HCC (87.5 %), theprevalence of type B in cancerous tissues was significantlyhigher than that in normal liver tissues (0/12) (P＜0.05), butthe prevalence of type A in cancerous tissues (46.88 %)was significantly lower than that in normal liver tissues(100.00 %) (P＜0.05), and the prevalence of type C (6.25 %)in cancerous was the same as that in normal liver tissues(25.00 %) (P＞0.05). In noncancerous tissues of livers withHCC, the main types were type A and type B, the prevalenceof type A (85.71%, 90.48 %) and type C (14.29 %, 9.52 %)in noncancerous tissues of liver with HCC was similar asthat in normal liver tissues (A: 100.00 %; C: 25.00 %)(P＞0.05), but the prevalence of type B (80.95 %, 76.19 %)in noncancerous tissues of livers with HCC was significantlyhigher than that in normal liver tissues (0/12) (P＜0.05). (5)The prevalence of type B (37.5 %) in peripheral blood withHCC was higher than that in normal person (0/12) (P＜0.05).In peripheral blood, type B was found in 4 of 11 cases ofHCC with serum AFP negative.CONCLUSION: The shift of types of GGTmRNA from A toB in liver tissues may be closely related to the developmentof HCC, and the analysis of GGT gene may provide a usefultool for early diagnosis of HCC.