title: Genetic variation of Varicella-Zoster Virus strains circulating in Mexico City.
abstract: BACKGROUND
  Different studies regarding VZV genotype distribution worldwide have demonstrated that genetic diversity and epidemiology of infection significantly vary from region to region. In Mexico, VZV genotype distribution is largely unknown mostly due to the lack of a surveillance system that monitors accurately the presence of viral strains circulating in the country.
  
  
  OBJECTIVE
  To identify the main VZV genotypes circulating in the metropolitan area of Mexico City.
  
  
  METHODS
  In this study, 127 different VZV isolates, obtained from residents of the Mexico City Metropolitan area from 2005 to 2008, were identified and genotyped. Viral detection and preliminary genotyping was performed by amplification of the VZV ORF-38 and -54 and RFLP analysis using PstI and BglI endonuclease restriction patterns, respectively. Genotype was confirmed by nucleotide sequence variation along the ORF-22.
  
  
  RESULTS
  RFLP analysis classified 121 viral strains as European and 6 as mosaic genotype. Genotyping scheme based on the ORF-22 sequence variation identified 120 viral strains belonging to the E genotype, 6 M1 and 1 M4 genotype strains.
  
  
  CONCLUSIONS
  VZV European genotype appears to predominate in Mexico City. This is the first study addressing VZV genotype distribution in Mexico. The information reported in this paper may be useful for future epidemiological studies conducted in the country and also contributes to understand better the molecular epidemiology of VZV in the Americas.
authors.affiliation: Departamento de Genoma de Patógenos, Instituto de Diagnóstico y Referencia Epidemiológicos, Secretaría de Salud, Mexico City, Mexico. aracelirc2@yahoo.com.mx
authors.forename: Araceli
authors.initials: A
authors.lastname: Rodríguez-Castillo
authors.forename: Gilberto
authors.initials: G
authors.lastname: Vaughan
authors.forename: José Ernesto
authors.initials: JE
authors.lastname: Ramírez-González
authors.forename: Elizabeth
authors.initials: E
authors.lastname: González-Durán
authors.forename: José Carmen
authors.initials: JC
authors.lastname: Gudiño-Rosales
authors.forename: Alejandro
authors.initials: A
authors.lastname: Escobar-Gutiérrez
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D014644:Genetic Variation; D005838:Genotype; D006562:Herpes Zoster / Q000453:epidemiology* / Q000821:virology*; D014645:Herpesvirus 3, Human / Q000145:classification* / Q000235:genetics*; D006801:Humans; D007223:Infant; D008297:Male; D008800:Mexico / Q000453:epidemiology; D008875:Middle Aged; D017720:Molecular Epidemiology; D055815:Young Adult