Abstract: Objective To observe the genotypes and resistance gene mutation of chronic hepatitis B virus in Sichuan to provide reference for antiviral therapy.Methods The index including HBV genotype,resistance gene mutation,liver function,HBeAg and HBV-DNA load of 489 patients with repeated abnormal liver function,who infected with chronic hepatitis B virus (CHB),in our hospital from Jan.2017 to Dec.2018 were examined.Results In our study,the age of patients were 11 to 82,the average was 40.31±7.64,and the number of male was more than female (332 men,67.89%).The main HBV genotype was type B (68.30%,334/489) and type C (27.61%,135/489),and there were 228 patients were founded drug-resistant mutation (58.90%,288/489),age from 13 to 75 (the average was 40.78±8.62).We found that the single site resistance gene mutation was 98 cases (34.03%,98/288),including the rtM204I(V) site mutation (36 cases),rtL180M mutation (31 cases) and rtN236T mutation (31 cases).The two sites mutation was totally 112 cases (38.89%,112/288),in which the most common mutation was rtL180M combined with rtM204I(V) (76 cases,67.86%,76/112).The three sites mutation was 78 cases (37.08%,78/288),which was based on rtL180M,rtM204 I(V) sites combined with rtN236T,rtA181V,rtA194T,rtS202 or rtM250.The drug resistance rate of type B was significantly higher than that of type C and other genotypes (χ²=10.38,P=0.005 6).Conclusion The main genotypes of HBV in Sichuan are type B and type C.Clinicians should be alert to the possibility of drug-resistant mutations in patients with repeated abnormal liver function and formulate individualized antiviral treatment plans according to the drug-resistant mutations.

Key words: Hepatitis B virus, Genotype, Drug-resistant mutation