Prevalence of DQ2, DQ8 and DR4 Alleles in Iraqi Celiac Patients
Celiac disease(CD) is a chronic small intestinal immune-mediated enteropathy precipitated by exposure to dietary gluten in genetically predisposed individuals, many environmental triggering factors are suggested to participate in its pathogenesis, CD is strongly concomitant with specific HLA class II genes known as HLA-DQ2 and HLA-DQ8 which present in 90-95% of celiac patients and the remaining (5-10%) bears DR4-DQ8 haplotype. Also non-HLA genes my influence susceptibility to the disease but their influence has not been confirmed yet. So that this study aims to determine the distribution of DQ2, DQ8, DR4and non DQ2/DQ8 among Iraqi celiac patients. Sample of 80 Iraqi celiac patients (tTg-A,tTg-G and AGA positive) has been chosen from all suspected patients who attending to Al-Suder- Medical city during the period of April 2015 to November 2015, blood samples were obtained from those patients and send for DNA extraction and HLA typing by RT-PCR. The results showed that 70% (56) patients were females and 30% (24) were males, also 37.5% from those patients were lies between 1-10 years old. HLA typing showed that 77.5% of those were had DQ2 genotyping, 7.5% were had D82 genotyping, 10% were had DR4-DQ8 genotyping and 5% were had non DQ2/DQ8 genotyping.
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