title: [Relationship between hepatitis B virus YMDD mutation and serum viral DNA loadings].
abstract: OBJECTIVE
  To investigate the relationship between lamivudine-resistant mutants of hepatitis B virus (HBV) and serum HBV DNA loading before antiviral therapy.
  
  
  METHODS
  This study involved 106 patients with hepatitis B receiving lamivudine treatment for an average of 32 months (rang 12-48 months). Serum HBV DNA loadings were measured with PCR before and every 4 to 6 months during lamivudine therapy. HBV YMDD mutants were detected using mismatched PCR-restriction fragment length polymorphism (PCR-RFLP) during lamivudine treatment.
  
  
  RESULTS
  HBV DNA loading was significantly higher in patients infected with HBV YMDD mutants during lamivudine therapy than those infected with HBV without YMDD mutation.
  
  
  CONCLUSIONS
  High viral loading in hepatitis B patients before treatment is associated with high likeliness of HBV YMDD mutation during lamivudine treatment. HBV DNA loading may be indicative for the occurrence of YMDD mutation during lamivudine therapy.
authors: Third People's Hospital of Jiujiang, Jiujiang 332000, China.
authors: Ling-He
authors: LH
authors: Kong
authors: Su-Xiang
authors: SX
authors: Gao
authors: Ya-Ping
authors: YP
authors: Gui
authors: Wen-Hong
authors: WH
authors: Liu
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology; D004279:DNA, Viral / Q000097:blood*; D024882:Drug Resistance, Viral / Q000235:genetics; D005260:Female; D006509:Hepatitis B / Q000097:blood; D006515:Hepatitis B virus / Q000187:drug effects / Q000235:genetics* / Q000502:physiology*; D006801:Humans; D019259:Lamivudine / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009154:Mutation; D019562:Viral Load / Q000235:genetics*
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D019259:Lamivudine