[The association of hepatitis B virus genotype and the basal core promoter mutation in Qidong, China].
OBJECTIVE
To investigate the prevalence of hepatitis B virus (HBV) genotypes and the association with hepatocellular carcinoma (HCC) or basal core promoter (BCP) mutation in Qidong, China.


METHODS
The whole genome of HBV or X gene sequences were obtained from serum samples of HBV infected patients by using PCR and direct sequencing methods. Phylogenetic tree was constructed to determine the genotypes or subgenotypes of HBV.


RESULTS
According to the phylogenetic tree constructed from full-length sequence of HBV, genotype C2 was predominant in Qidong area. It was prevalent in 44 out of the 48 cases (91.7%), whereas genotype B2 only existed in 4 cases (8.3%). No other genotypes or recombinant types were found in Qidong patients. The result of genotyping based on X gene sequence confirmed the above observation. In a total of 182 samples, 169 (92.9%) showed genotype C2 and 10 (5.5%) showed genotype B2. There were 3 (1.6%) patients showed a coinfection with C2 and B2. The infection rate of genotype C in Qidong was significantly higher than that in neighboring city Shanghai (chi(2) = 12.252, P less than 0.01). There was no significant difference of genotype distribution between HCC and chronic hepatitis groups (P is more than 0.05). The frequency of T1762/A1764 double mutation in genotype C2 (70.3%) was significantly higher than that in genotype B2 (30.8%, P less than 0.05). The other two types of point mutation which also occurred in BCP, i.e. T1766 and A1768, were only seen in genotype C2.


CONCLUSIONS
(1) Genotype C2 is the predominant genotype in Qidong, China. (2) There is no association between genotype C and HCC in Qidong. (3) Genotype C has a higher prevalence of BCP mutation than genotype B.
Jin
Yan
Y
State Key Laboratory of Oncogenes and Related Genes, Cancer Institute, Medical School of Shanghai Jiaotong University, Shanghai 200032, China.
Zhu
Yu
Y
Chen
Tao-yang
TY
Guo
Xia
X
Zhang
Jing
J
Wang
Jin-bing
JB
Chen
Wei-zhong
WZ
Qian
Geng-sun
GS
Tu
Hong
H
D000293:Adolescent; D000328:Adult; D000368:Aged; D006528:Carcinoma, Hepatocellular / Q000453:epidemiology / Q000821:virology*; D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D004279:DNA, Viral / Q000235:genetics; D005260:Female; D005838:Genotype; D006515:Hepatitis B virus / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000821:virology; D006801:Humans; D008113:Liver Neoplasms / Q000453:epidemiology / Q000821:virology*; D008297:Male; D008875:Middle Aged; D009154:Mutation; D015995:Prevalence; D014758:Viral Core Proteins / Q000235:genetics*; D055815:Young Adult
D004279:DNA, Viral; D014758:Viral Core Proteins