Pattern of human leukocyte antigens in Turkish children with celiac disease

Background : Regional variations in the human leukocyte antigen (HLA) distribution patterns of celiac disease (CD) have been reported. The aim of the present study was to assess the distribution of HLA class I and class II in Turkish children with CD and to compare the findings with a control group. Methods : Human leukocyte antigen typing was performed in 33 children with CD and in 77 healthy individuals, who served as controls, by using standard National Institutes of Health lymphocytotoxicity techniques. Results : A positive association was found between HLA A2 (42 vs 19% for sick subjects compared with healthy controls, respectively), B8 (39 vs 9% for sick subjects compared with healthy controls, respectively), CW7 (45 vs 25% for sick subjects compared with healthy controls, respectively), DR3 (70 vs 17% for sick subjects compared with healthy controls, respectively), DR7 (30 vs 13% for sick subjects compared with healthy controls, respectively) and DQ2 (52 vs 34% for sick subjects compared with healthy controls, respectively). The combinations of DR3–DQ2 (30 vs 12% for sick subjects compared with healthy controls, respectively), DR3–DR4 (21 vs 1% for sick subjects compared with healthy controls, respectively) and DR7–DQ2 (21 vs 6% for sick subjects compared with healthy controls, respectively) were also found to be significantly important in children with CD. The highest relative risk (RR) was for HLA B8 in class I (RR 6.50), for DR3 (RR 11.30) in class II and for combination of DR3–DR4 (RR 20.46). The highest etiologic fraction (EF) was for the DR3 antigen (EF 0.55). Conclusions : The present study emphasizes that HLA genotypes are an important background to CD development, but some additional susceptibility factors remain to be identified.