title: Role of the HLA system in the association between multiple sclerosis and infectious mononucleosis.
abstract: OBJECTIVE
  To determine whether multiple sclerosis (MS) and infectious mononucleosis (IM) share common HLA associations.
  
  
  METHODS
  A prospective cohort study was conducted from October 1, 1999, through September 30, 2003.
  
  
  METHODS
  University of Edinburgh Richard Verney Health Centre, Edinburgh, Scotland.
  
  
  METHODS
  Participants included 179 individuals who underwent asymptomatic Epstein-Barr virus seroconversion and 175 patients who developed IM.
  
  
  METHODS
  Genotyping for 5 classical HLA loci (HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1).
  
  
  METHODS
  Diagnosis of IM and allele frequency.
  
  
  RESULTS
  Allelic analysis showed that HLA-DRB1*01:01 was significantly associated with the development of IM (odds ratio, 3.2; P < .001). Patients with IM and HLA-DRB1*01:01 had a lower Epstein-Barr virus viral load compared with those without the allele (median, 783 vs 7366 copies/10(6) peripheral blood mononuclear cells; P = .03).
  
  
  CONCLUSIONS
  HLA-DRB1*01:01 is protective against developing MS; thus, a common genetic basis between IM and MS is not supported.
authors.affiliation: Blizard Institute of Cell and Molecular Science, Queen Mary University of London, Barts and The London School of Medicine and Dentistry, England, UK.
authors.forename: Sreeram V
authors.initials: SV
authors.lastname: Ramagopalan
authors.forename: Ute C
authors.initials: UC
authors.lastname: Meier
authors.forename: Margaret
authors.initials: M
authors.lastname: Conacher
authors.forename: George C
authors.initials: GC
authors.lastname: Ebers
authors.forename: Gavin
authors.initials: G
authors.lastname: Giovannoni
authors.forename: Dorothy H
authors.initials: DH
authors.lastname: Crawford
authors.forename: Karen A
authors.initials: KA
authors.lastname: McAulay
mesh_terms: D015331:Cohort Studies; D005838:Genotype; D015234:HLA-A Antigens / Q000235:genetics / Q000502:physiology*; D059811:HLA-DRB1 Chains; D006239:Haplotypes / Q000235:genetics; D004854:Herpesvirus 4, Human / Q000235:genetics / Q000472:pathogenicity; D006801:Humans; D007244:Infectious Mononucleosis / Q000235:genetics / Q000276:immunology* / Q000517:prevention & control; D009103:Multiple Sclerosis / Q000235:genetics / Q000276:immunology* / Q000517:prevention & control; D011446:Prospective Studies; D012307:Risk Factors; D019562:Viral Load / Q000235:genetics
chemical_list: D015234:HLA-A Antigens; D059811:HLA-DRB1 Chains; C487961:HLA-DRB1*01:01 antigen