title: Frequency of chromosomally-integrated human herpesvirus 6 in children with acute lymphoblastic leukemia.
abstract: BACKGROUND
  Human herpesvirus 6 (HHV-6) is a ubiquitous pathogen infecting nearly 100% of the human population. Of these individuals, between 0.2% and 1% of them carry chromosomally-integrated HHV-6 (ciHHV-6). The biological consequences of chromosomal integration by HHV-6 remain unknown.
  
  
  OBJECTIVE
  To determine and compare the frequency of ciHHV-6 in children with acute lymphoblastic leukemia to healthy blood donors.
  
  
  METHODS
  A total of 293 DNA samples from children with pre-B (n=255), pre-pre-B (n=4), pre-T (n=26) and undetermined (n=8) leukemia were analyzed for ciHHV-6 by quantitative TaqMan PCR (QPCR) using HHV-6 specific primers and probe. As control, DNA samples from 288 healthy individuals were used. Primers and probe specific to the cellular GAPDH gene were used to estimate integrity and DNA content.
  
  
  RESULTS
  Out of 293 DNA samples from the leukemic cohort, 287 contained amplifiable DNA. Of these, only 1 (0.35%) contained ciHHV-6. Variant typing indicates that the ci-HHV-6 corresponds to variant A. None of the 288 DNA samples from healthy individuals contained ciHHV-6.
  
  
  CONCLUSIONS
  The frequency of ciHHV-6 in children with acute lymphoblastic leukemia is similar (p=0.5) to that of healthy individuals. These results suggest that acute lymphoblastic leukemia does not originate as a consequence to integration of HHV-6 within the chromosomes.
authors.affiliation: Division of Infectious Diseases and Immunity, CHU de Quebec Research Center, Quebec, Canada.
authors.forename: Annie
authors.initials: A
authors.lastname: Gravel
authors.affiliation: Centre de recherche, Service d'hématologie-oncologie, CHU Sainte-Justine, Département de pédiatrie, Université de Montréal, Montreal, Quebec, Canada.
authors.forename: Daniel
authors.initials: D
authors.lastname: Sinnett
authors.affiliation: Division of Infectious Diseases and Immunity, CHU de Quebec Research Center, Quebec, Canada ; Department of Microbiology, Infectious Diseases and Immunology, Laval University, Quebec, Quebec, Canada.
authors.forename: Louis
authors.initials: L
authors.lastname: Flamand
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002877:Chromosomes, Human / Q000235:genetics / Q000821:virology*; D005260:Female; D015654:Herpesvirus 6, Human / Q000502:physiology*; D006801:Humans; D008297:Male; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000235:genetics* / Q000821:virology*; D012307:Risk Factors; D016662:Virus Integration