Case Control Study
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World J Gastroenterol. May 28, 2014; 20(20): 6302-6308
Published online May 28, 2014. doi: 10.3748/wjg.v20.i20.6302
Allele and haplotype frequencies for HLA-DQ in Iranian celiac disease patients
Mohammad Rostami-Nejad, Jihane Romanos, Kamran Rostami, Azita Ganji, Mohammad Javad Ehsani-Ardakani, Ali-Reza Bakhshipour, Homayoun Zojaji, Seyed Reza Mohebbi, Mohammad-Reza Zali, Cisca Wijmenga
Mohammad Rostami-Nejad, Mohammad Javad Ehsani-Ardakani, Homayoun Zojaji, Seyed Reza Mohebbi, Mohammad-Reza Zali, Department of Celiac Disease, Gastroenterology and Liver Diseases Research Centers, Shahid Beheshti University of Medical Sciences, Tehran 1985717411, Iran
Jihane Romanos, Cisca Wijmenga, Department of Genetics, University of Groningen, University Medical Centre of Groningen, 9700 RB Groningen, The Netherlands
Kamran Rostami, Department of Gastroenterology, Worcestershire Royal Hospital, Worcester, WR5 1DD, United Kingdom
Azita Ganji, Department of Gastroenterology, Imam Reza Hospital Mashhad University of Medical Sciences, Mashhad 1351143, Iran
Ali-Reza Bakhshipour, Department of Gastroenterology, Zahedan University of Medical Sciences, Zahedan 2143453, Iran
Jihane Romanos, Department of Genetics, Institute of Human Genetics, Lebanese American University, Byblos 36, Lebanon
Author contributions: Rostami-Nejad M contributed to sample collection, article writing, final approval; Romanos J contributed to HLA typing and drafting the article; Rostami K contributed to supervisor of this project and editing the manuscript; Ganji A contributed to sample collection from Mashhad city; Mohebbi SR contributed to DNA extraction and analysis and interpretation of data; Zojaji H contributed to Sample collection from Tehran city; Bakhshipour AR contributed to sample collection from Zahedan city; Zali MR and Ehsani-Ardakani MJ contributed to concept and design of the work, final approval; Wijmenga C contributed to supervising HLA typing, article writing, final approval.
Correspondence to: Mohammad Javad Ehsani-Ardakani, MD, Department of Celiac Disease, Gastroenterology and Liver Diseases Research Centers, Shahid Beheshti University of Medical Sciences, Velenjak St., Shahid Chamran Highway, Tehran 1985717411, Iran. mjehsani@yahoo.com
Telephone: +98-21-22432518 Fax: +98-21-22432517
Received: November 2, 2013
Revised: December 31, 2013
Accepted: January 20, 2014
Published online: May 28, 2014
Processing time: 206 Days and 20.2 Hours
Abstract

AIM: To assess the distribution of human leukocyte antigen (HLA)-DQ2 and -DQ8 in Iranian celiac disease (CD) patients and compare them to healthy Iranian controls.

METHODS: To predict the HLA-DQA1 and -DQB1 genes, we used six previously reported HLA-tagging single nucleotide polymorphism to determine HLA genotypes in 59 Iranian patients with ‘biopsy-confirmed’ CD and in 151 healthy Iranian individuals. To test the transferability of the method, 50 cases and controls were also typed using a commercial kit that identifies individual carriers of DQ2, DQ7 and DQ8 alleles.

RESULTS: In this pilot study 97% of CD cases (n = 57) and 58% of controls (n = 87) were carriers of HLA-DQ2 and/or HLA-DQ8 heterodimers, either in the homozygous or heterozygous state. The HLA-DQ pattern of these 57 CD patients: heterozygous DQ2.2 (n = 14) and homozygous DQ2.2 (n = 1), heterozygous DQ2.5 (n = 33) and homozygous DQ2.5 (n = 8), heterozygous DQ8 (n = 13) and homozygous DQ8 (n = 2). Two CD patients were negative for both DQ2 and DQ8 (3%).

CONCLUSION: The prevalence of DQ8 in our CD population was higher than that reported in other populations (25.4%). As reported in other populations, our results underline the primary importance of HLA-DQ alleles in the Iranian population’s susceptibility to CD.

Keywords: Human leukocyte antigen typing; Validation; Susceptibility; Celiac disease; Iran

Core tip: We describe, for the first time, the distribution of human leukocyte antigen (HLA)-DQ2/DQ8 alleles in Iranian celiac disease patients compared to healthy Iranian controls. To assess this distribution we applied a single nucleotide polymorphism-based approach, which was developed in European (Caucasian) study samples. We also demonstrate the transferability of such an approach to the Iranian population. Our results underline the primary importance of HLA-DQ alleles in the Iranian population’s susceptibility to celiac disease.