title: Prevalence of the Taiwan variant of the Epstein-Barr virus in nasopharyngeal carcinoma patients and normal individuals.
abstract: BACKGROUND
  Latent membrane protein 1 (LMP1) of Epstein-Barr virus (EBV) is a potentially oncogenic protein, able to inhibit differentiation and induce transformation of epithelial cells. The LMP1 gene sequence of EBV in nasopharyngeal carcinoma (NPC) differs from that of EBV in B95-8 cells. A change of nucleotide at the XhoI site results in loss of the restriction site in the EBV LMP1 gene from NPC, and this of EBV is designated as the Taiwan variant. In this study, we further investigated the Taiwan variant of EBV in nasopharyngeal biopsies and throat washings of NPC patients and normal controls.
  
  
  METHODS
  DNA was extracted from nasopharyngeal biopsies of 22 NPC patients and 40 normal controls, and from throat washings of 28 NPC patients and 78 normal controls. The DNA was amplified by polymerase chain reaction (PCR) using LMP1 gene-specific primers, then the EBV variant was identified by analysis with the XhoI restriction enzyme.
  
  
  RESULTS
  The LMP1 gene was detected in all NPC tumors, in only 25 of 40 normal nasopharyngeal biopsies, and in 12 of 28 and 44 of 78, respectively, throat washings of NPC patients and normal controls. The Taiwan variant was detected in 84.1% to 100% of EBV isolates. The distribution of Taiwan variant EBV was not statistically different between the NPC group and normal controls in either nasopharyngeal biopsies or throat washings.
  
  
  CONCLUSIONS
  The results indicate that, based on XhoI restriction site analysis, the Taiwan variant of EBV is the predominant EBV strain in NPC patients and normal individuals in Taiwan.
authors.affiliation: Department of Otolaryngology, Taipei Veterans General Hospital, Taiwan, ROC.
authors.forename: C H
authors.initials: CH
authors.lastname: Shu
authors.forename: T Y
authors.initials: TY
authors.lastname: Tu
mesh_terms: D001483:Base Sequence; D004279:DNA, Viral / Q000032:analysis; D004854:Herpesvirus 4, Human / Q000145:classification* / Q000302:isolation & purification; D006801:Humans; D008969:Molecular Sequence Data; D009303:Nasopharyngeal Neoplasms / Q000821:virology*; D016133:Polymerase Chain Reaction; D013624:Taiwan
chemical_list: D004279:DNA, Viral