title: High Frequency of Haplotype HLA-DQ7 in Celiac Disease Patients from South Italy: Retrospective Evaluation of 5,535 Subjects at Risk of Celiac Disease.
abstract: BACKGROUND
  Celiac disease (CD) has a strong genetic component mainly due to HLA DQ2/DQ8 encoding genes. However, a minority of CD patients are DQ2/DQ8-negative. To address this issue, we retrospectively characterized HLA haplotypes in 5,535 subjects at risk of CD (either relatives of CD patients or subjects with CD-like symptoms) referred to our center during a 10-year period.
  
  
  METHODS
  We identified loci DQA1/DQB1/DRB1 by sequence-specific oligonucleotide-PCR and sequence-specific primer-PCR; anti-transglutaminase IgA/IgG and anti-endomysium IgA by ELISA and indirect immunofluorescence, respectively.
  
  
  RESULTS
  We diagnosed CD in 666/5,535 individuals, 4.2% of whom were DQ2/DQ8-negative. Interestingly, DQ7 was one of the most abundant haplotypes in all CD patients and significantly more frequent in DQ2/DQ8-negative (38%) than in DQ2/DQ8-positive CD patients (24%) (p<0.05).
  
  
  CONCLUSIONS
  Our data lend support to the concept that DQ7 represents an additive or independent CD risk haplotype with respect to DQ2/DQ8 haplotypes but this finding should be verified in other large CD populations.
authors.affiliation: Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy; CEINGE-Advanced Biotechnology, s. c. a r. l., Naples, Italy.
authors.forename: Nadia
authors.initials: N
authors.lastname: Tinto
authors.affiliation: Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy; CEINGE-Advanced Biotechnology, s. c. a r. l., Naples, Italy.
authors.forename: Arturo
authors.initials: A
authors.lastname: Cola
authors.affiliation: Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy; CEINGE-Advanced Biotechnology, s. c. a r. l., Naples, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Piscopo
authors.affiliation: Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy; CEINGE-Advanced Biotechnology, s. c. a r. l., Naples, Italy.
authors.forename: Marina
authors.initials: M
authors.lastname: Capuano
authors.affiliation: Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Naples, Italy; Department of Translational Medical Sciences, Section of Pediatrics, University of Naples "Federico II", Naples, Italy.
authors.forename: Martina
authors.initials: M
authors.lastname: Galatola
authors.affiliation: Department of Translational Medical Sciences, Section of Pediatrics, University of Naples "Federico II", Naples, Italy.
authors.forename: Luigi
authors.initials: L
authors.lastname: Greco
authors.affiliation: CEINGE-Advanced Biotechnology, s. c. a r. l., Naples, Italy.
authors.forename: Lucia
authors.initials: L
authors.lastname: Sacchetti
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002446:Celiac Disease / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006683:HLA-DQ Antigens / Q000235:genetics*; D006239:Haplotypes / Q000235:genetics*; D006801:Humans; D007558:Italy; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult
chemical_list: D006683:HLA-DQ Antigens; C069546:HLA-DQ7 antigen