title: Frequency distribution of HLA DQ2 and DQ8 in celiac patients and first-degree relatives in Recife, northeastern Brazil.
abstract: OBJECTIVE
  The aim of this study was to evaluate the frequencies of the HLA genotypes DQ2 and DQ8 and the alleles A1*05, A1*0201, B1*0201 and B1*0302 in individuals with celiac disease in Recife, northeastern Brazil.
  
  
  METHODS
  HLA DQ2 and DQ8 genotyping was performed for 73 individuals with celiac disease and 126 first-degree relatives with negative transglutaminase serology. The alleles DQA1*05, DQA1*0201, DQB1*02 and DQB1*0302 were identified by sequencing using specific primers and the EU-DQ kit from the Eurospital Laboratory, Trieste, Italy and double-checked by the All Set SPP kit (Dynal).
  
  
  RESULTS
  Among the 73 cases, 50 (68.5%) had the genotype DQ2, 13 (17.8%) had DQ8, 5 (6.8%) had DQ2 and DQ8, and 5 did not have any of these genotypes. Among the 5 negative individuals, four had the B1*02 allele and one did not have any of the alleles studied. B1*02 was the most frequent allele in both groups (94% in the patients and 89% in the control relatives).
  
  
  CONCLUSIONS
  In this study, celiac disease was associated with the genotypes DQ2 and DQ8. DQ2 predominated, but the distribution of the frequencies was different from what has been found in European populations and was closer to what has been found in the Americas. The high frequencies of the HLA genotypes DQ2 and DQ8 that were found in first-degree relatives would make it difficult to use these HLA genotypes for routine diagnosis of celiac disease in this group.
authors.affiliation: Department of Postgraduate Studies on Children and Adolescents' Health, Health Sciences Center, Federal University of Pernambuco. margarida.mmcastro@gmail.com
authors.forename: Margarida Maria
authors.initials: MM
authors.lastname: Castro-Antunes
authors.forename: Sergio
authors.initials: S
authors.lastname: Crovella
authors.forename: Lucas Andre Cavalcanti
authors.initials: LA
authors.lastname: Brandão
authors.forename: Rafael Lima
authors.initials: RL
authors.lastname: Guimaraes
authors.forename: Maria Eugênia Farias Almeida
authors.initials: ME
authors.lastname: Motta
authors.forename: Giselia Alves Pontes da
authors.initials: GA
authors.lastname: Silva
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil / Q000453:epidemiology; D002446:Celiac Disease / Q000235:genetics*; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005060:Europe / Q000453:epidemiology; D005190:Family; D005260:Female; D005787:Gene Frequency / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000453:epidemiology / Q000235:genetics*; D006683:HLA-DQ Antigens / Q000235:genetics*; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D055815:Young Adult
chemical_list: D006683:HLA-DQ Antigens; C053186:HLA-DQ2 antigen; C109756:HLA-DQ8 antigen