HLA class II high-resolution genotyping in Greek children with celiac disease and impact on disease susceptibility.

Background: Celiac disease (CD) has been associated with HLA class II heterodimers. This study aimed at determining the HLA genotypic and allelic distribution in Greek children with CD as compared with the general population.

Methods: A total of 118 children with CD and 120 healthy individuals serving as controls were included in the study.

Results: Higher frequencies for HLA-DQB1*02:01 (40.25 vs. 9.58%, P < 0.001) and DQB1*02:02 (20.34 vs. 5.42%, P < 0.001) were observed in patients with CD, whereas HLA-DQB1*03:01 (16.53 vs. 30.42%, P < 0.001), DQB1*05:01 (0.85 vs. 10%, P < 0.001), and DQB1*05:02 (5.51 vs. 17.92%, P < 0.001) were significantly lower, as compared with the controls. DQA1*02:01 (patients with CD vs. controls: 20.76 vs. 6.67%, P < 0.001) and DQA1*05:01 (40.25 vs. 9.58%, P < 0.001) were significantly more frequent in patients. The frequencies of HLA-DQA1* 01:01, *01:02, *01:04, and *05:05 were significantly lower in patients (P < 0.001). The haplotype mainly associated with CD was DRB1*03-DQB1*02:01-DQA1*05:01; patients with CD vs. controls: 39.83 vs. 9.58%, P < 0.001. In total, 84.75% of patients carried DQ2 (vs. 21.67% in controls, P < 0.001), whereas 11.02% were DQ8 positive/DQ2 negative.

Conclusion: This study confirms the existing data and provides additional evidence supporting a strong genetic predisposition for CD associated with the class II alleles DQB1*02 and DQA1*05 encoding the serological specificity DQ2.