title: HLA genotyping is useful in the evaluation of the risk for coeliac disease in the 1st-degree relatives of patients with coeliac disease.
abstract: OBJECTIVE
  Coeliac disease (CD) is a common disease with a strong heredity. About 10-20% of 1st-degree relatives of probands develop CD. Relatives should be screened for CD, because if not treated, CD exposes patients to numerous complications. The heterogeneity of symptoms and the lifetime-spanning risk of CD render the timing of CD antibody and/or gastroscopy screenings difficult. As CD susceptibility has been shown to be strongly associated with the HLA alleles DQA1*0501 and DQB1*0201 (together encoding the DQ2 heterodimer) and DRB1*04 (associated with the DQ8 heterodimer), our aim was to investigate whether HLA genotyping might be useful in the identification of 1st-degree relatives of CD patients who do not need further screening for CD.
  
  
  METHODS
  The study comprised 54 Finnish CD families including 54 CD probands and 382 living 1st-degree relatives. All subjects who were willing to participate were screened for CD (duodenal and skin biopsies; endomysial, reticulin and gliadin antibodies). The DQA1*0501, DQB1*0201 and DRB1*04 allele frequencies of CD patients and the 1st-degree relatives were determined.
  
  
  RESULTS
  Altogether 17.6% (5.9% of the parents, 15.7% of the siblings, 25.8% of the offspring) of the investigated 1st-degree relatives (n = 245) did not carry any of the alleles studied. All of the CD patients (n = 136) with the exception of one (0.7%) carried at least one of the alleles investigated.
  
  
  CONCLUSIONS
  By using the HLA genotyping a considerable proportion of 1st-degree relatives of CD probands could be excluded from further screening for CD.
authors.affiliation: Department of Medicine, University of Kuopio and Kuopio University Hospital, Kuopio, Finland. hannele.karinen@fimnet.fi
authors.forename: Hannele
authors.initials: H
authors.lastname: Karinen
authors.forename: Päivi
authors.initials: P
authors.lastname: Kärkkäinen
authors.forename: Jussi
authors.initials: J
authors.lastname: Pihlajamäki
authors.forename: Esko
authors.initials: E
authors.lastname: Janatuinen
authors.forename: Markku
authors.initials: M
authors.lastname: Heikkinen
authors.forename: Risto
authors.initials: R
authors.lastname: Julkunen
authors.forename: Veli-Matti
authors.initials: VM
authors.lastname: Kosma
authors.forename: Anita
authors.initials: A
authors.lastname: Naukkarinen
authors.forename: Markku
authors.initials: M
authors.lastname: Laakso
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D002446:Celiac Disease / Q000175:diagnosis / Q000453:epidemiology / Q000235:genetics*; D002648:Child; D002675:Child, Preschool; D005190:Family; D005260:Female; D005387:Finland / Q000453:epidemiology; D020022:Genetic Predisposition to Disease; D005820:Genetic Testing; D005838:Genotype; D006680:HLA Antigens / Q000235:genetics*; D006683:HLA-DQ Antigens / Q000235:genetics; D006684:HLA-DR Antigens / Q000235:genetics; D059811:HLA-DRB1 Chains; D006801:Humans; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D012189:Retrospective Studies; D018570:Risk Assessment
chemical_list: D006680:HLA Antigens; D006683:HLA-DQ Antigens; D006684:HLA-DR Antigens; D059811:HLA-DRB1 Chains