HLA-DQ2 and HLA-DQ8 Genotyping in a Sample of Iranian Celiac Patients and Their First-Degree Relatives

Abstract

Background

Recent studies have shown a critical role for HLA-DQ2 and HLA-DQ8 in the pathogenesis of celiac disease. No study has been performed on the prevalence of these two HLA types in Iranian celiac patients.

Materials and Methods

We enrolled 24 celiac patients and 37 first-degree relatives in whom the diagnosis of celiac was excluded by serologic tests. HLA typing for HLA-DQ2 (DQB1*02), HLA-DQ8 (DQB1*03), HLA-DQ B1*05 and HLA-DQ B1*06 was performed using polymerase chain (PCR) reaction.

Results

Twenty two (91.7%) celiac patients and twenty seven (73%) controls were positive for the HLA-DQ2 and/or HLA-DQ8 heterodimers. There was no significant difference between the two groups (p=0.068). However, celiac patients were statistically more positive for homozygote HLA-DQ2, whereas non-celiac participants were more positive for homozygote HLA-DQ8 (p<0.05).

Conclusion

The total prevalence of HLA-DQ2 and/or HLA-DQ8 alleles did not significantly differ between the two groups. Hence, first-degree relatives of celiac patients appear to be more susceptible for developing celiac disease. On the other hand, the higher prevalence of homozygote HLA-DQ2 in celiac patients shows its stronger role in disease pathogenesis. Further studies on larger populations are needed in Iran.