title: Human papillomavirus type 16 E2 and E6/E7 variants.
abstract: OBJECTIVE
  Polymorphisms in human papillomavirus (HPV) type 16 have been shown to be related to geographic areas and are broadly classified as European (E), African (Af), Asian (As), or Asian-American (AA). Certain variants have been reported as being more likely to cause cervical disease; our objectives were to identify new HPV16 polymorphisms, to determine the linkage of the E2 and E6/E7 regions and to determine the minimum sequence necessary to classify variants.
  
  
  METHODS
  We sequenced the complete E2, E6, and E7 regions in all HPV16-positive cervical samples identified in a case-control study of pre-invasive cervical disease.
  
  
  RESULTS
  In the 100 samples analyzed, only one new polymorphism was identified, a synonymous change, T3205A, in region E2. The frequency distribution of variants in the sample set was 37 European prototypes and 27 E-G350, 16 AA, 5 Af1, 2 Af2, 8 E-C109G, 3 E-G131G, and 2 As. As shown by others, region E7 varied much less than E6 and E2.
  
  
  CONCLUSIONS
  In each case, E2 changes were linked to the expected E6/E7 changes, and there was no evidence for recombination. The linkage between E2 and E6/E7 allows variant classification to be based on a short E6 sequence (nt 109-350).
authors.affiliation: U.S. Department of Health and Human Services, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, Atlanta, GA 30333, USA. dswan@cdc.gov
authors.forename: David C
authors.initials: DC
authors.lastname: Swan
authors.forename: Mangalathu
authors.initials: M
authors.lastname: Rajeevan
authors.forename: Guillermo
authors.initials: G
authors.lastname: Tortolero-Luna
authors.forename: Michele
authors.initials: M
authors.lastname: Follen
authors.forename: Ruth Ann
authors.initials: RA
authors.lastname: Tucker
authors.forename: Elizabeth R
authors.initials: ER
authors.lastname: Unger
mesh_terms: D001483:Base Sequence; D016022:Case-Control Studies; D004279:DNA, Viral / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D006801:Humans; D009856:Oncogene Proteins, Viral / Q000235:genetics; D027383:Papillomaviridae / Q000235:genetics*; D050725:Papillomavirus E7 Proteins; D030361:Papillomavirus Infections / Q000821:virology; D011110:Polymorphism, Genetic; D012097:Repressor Proteins / Q000235:genetics; D014412:Tumor Virus Infections / Q000821:virology; D002583:Uterine Cervical Neoplasms / Q000821:virology*; D002578:Uterine Cervical Dysplasia / Q000821:virology*
chemical_list: D004279:DNA, Viral; D004268:DNA-Binding Proteins; C054855:E2 protein, Human papillomavirus type 16; C068651:E6 protein, Human papillomavirus type 16; D009856:Oncogene Proteins, Viral; D050725:Papillomavirus E7 Proteins; D012097:Repressor Proteins; C059731:oncogene protein E7, Human papillomavirus type 16