The Research Of HBV Genotypes And Nucleotide Analogues Resistant Mutation

HBV(hepatitis B virus)acts as the main inducing factor of liver cirrhosis and liver cancer in China。HBV was divided into 10 genotypes(A、B、C、D、E、F、G、H、I、J)according to the heterogeneity of whole genome sequences(heterogeneity≥8%)or S gene sequence(heterogeneity≥4%).HBV genotype is associated with clinical manifestations and drug resistance.The special structure of HBV DNA leading to efficient natural mutation of HBV.HBV was replicated and packaged in the cell,thus it can’t to be cleared in short time and difficult to be effected by drug.Nowadays,main drugs for the treating HBV are interfere and nucleotide analogues(NAs).NAs are widly used as for better effect and oral administration.NAs resistance mutations will occurred in polymerase and reverse transcriptase area after long term treatment of NAs.Nevertheless,some research has shown that resistance mutations were also detected in serum HBV of non-treated patients.Genotype distribution and drug resistance mutation rate is different between non-treated patients and treated patients.Furthermore,HBV DNA loads of non-treated patients was correlated with genotype and drug resistance mutations.Detection of genotype and drug resistance mutation could provide useful messages before or during the process of clinical treatment.Objective:1.HBV genotype and NAs resistance mutations were detected and compared between non-treated and treated patients,in order to formulate reasonable therapy protocol.2.The relationship of HBV DNA loads,genotype and NAs resistance mutations were explored in non-treated patients to prepare treatment program for non-treated patients..Methods:Genotype and drug resistance loci of HBV is detected by PCR reverse spot hybridization method in 74 non-treated patients and 66 treated patients.Then,205non-treated cases were collected and HBV DNA loads,genotype and drug resistance loci were detected.All cases were divided into three groups according to DNA loads(high,middle and low).Genotype distribution and drug resistance mutations were analysed between three groups.Lastly,gene sequencing were conducted in randomly selected 20 samples,and sequencing results compared with the results of reverse spot hybridization.Statistical analysis were performed by SPSS16.0 software.Results : 1.Composition of non-treated patients and treated patients(HBV DNA >103IU/ml): 49 male and 25 female in non-treated group,age(36.432±12.941);53 male and 13 female in treated group,age(38.667±14.812).66.216% and 59.091% HBV Btype were discorved in non-treated group and treated group.ADV resistance acted as the main resistance mutation loci in non-treated group and LAM resistance in treated group.The ratio of drug resistance mutations in non-treated group was lower than that in treated group(χ2=4.268,P =0.0388).The ratio of multiple drug resistance mutations in non-treated group(4 cases,5.405%)was lower than that in treated group(16 cases,24.242%,P <0.05).2.there were 205 non-treated cases(127 male,78 female;age 36.79±13.39).HBV B acted as the main genotype in non-treat patients.Furthermore,HBV B is given priority to low HBV DNA loads group and C type give priority to high HBV DNA loads group.Drug resistance were not detected in all HBV from low DNA loads group.Drug resistance was statistically difference between high DNA loads group(7 cases)and middle DNA loads group(43 cases,P <0.05).Drug resistance mutations in C type and mixed genotype(B/C;B/D)were only detected in high HBV DNA loads group.Drug resistance mutation of HBV B genotype was statistically difference between high DNA loads group and middle DNA loads group(P <0.05).Conclusion:1.HBV B acts as the main genotype in non-treated patients and treated patients.The ratio of multiple drug resistance mutations in non-treated group is lower than that in treated group..2.Certain relationship is detected between HBV DNA loads and HBV genotype as well as drug resistance loci in non-treated patients.Drug resistance mainly occurs in middle DNA loads group and concentrated in mixed genotype.Therefore,the results could provide important massage to formulate reasonable clinical therapy protocol.