Anil K Verma1, John Mechenro2,3, Chiara Monachesi4, Giriprasad Venugopal2,3, Giulia Naspi Catassi5, Elena Lionetti5, Balakrishnan S Ramakrishna2,3, Carlo Catassi5,6. 1. Celiac Disease Research Laboratory, Department of Pediatrics, Università Politecnica delle Marche, 60123, Ancona, Italy. anilkrvermaa@gmail.com. 2. SRM Institute of Gastroenterology, Hepatobiliary Sciences and Transplantation, SIMS Hospital, Jawaharlal Nehru Road, Vadapalani, Chennai, 600 026, India. 3. Department of Medical Research, SRM Medical College Hospital and Research Centre, Kancheepuram District, Kattankulathur, 603 211, India. 4. Celiac Disease Research Laboratory, Department of Pediatrics, Università Politecnica delle Marche, 60123, Ancona, Italy. 5. Department of Pediatrics, Università Politecnica delle Marche, 60123, Ancona, Italy. 6. The Division of Pediatric Gastroenterology and Nutrition and Center for Celiac Research, Mass General Hospital for Children, Boston, MA, 02114, USA.
Abstract
BACKGROUND: Celiac disease (CD) is an intestinal inflammatory condition caused by the ingestion of gluten peptides in wheat and related grains in individuals carrying HLA-DQ2 and/or HLA-DQ8 genes. In comparison to HLA-DQ8, a higher HLA-DQ2 prevalence is reported in European population where wheat has been the staple food for thousands of years. In non-European population, this pattern of HLA-DQ CD-predisposing gene distribution has not always been found. The aim of this study was to evaluate the HLA-DQ2 and HLA-DQ8 distribution in the native low-gluten consuming southern Indian population. METHODS: Overall, 211 dried blood spots (DBS) were collected from native southern Indian individuals. HLA-DQ characterization and the determination of homozygous/heterozygous status were performed using commercially available HLA-DQ typing kits. RESULTS: Of 211 collected DBS, 88 (42%, 95% CI: 36-48) were positive for HLA-DQ2 and/or HLA-DQ8 heterodimers. Overall, 40 (19%, 95% CI: 14-24) samples typed positive for HLA-DQ2 and 48 (23%, 95% CI: 18-28) typed positive for HLA-DQ8 genotypes. Of 40 HLA-DQ2-positive individuals, only one subject tested homozygous for the DQB1*02 allele. CONCLUSIONS: In the southern Indian native general population, the prevalence of HLA-DQ8 is higher in comparison to HLA-DQ2 prevalence. This finding could be related to the delayed introduction of wheat in the diet of the southern Indian population.
BACKGROUND: Celiac disease (CD) is an intestinal inflammatory condition caused by the ingestion of gluten peptides in wheat and related grains in individuals carrying HLA-DQ2 and/or HLA-DQ8 genes. In comparison to HLA-DQ8, a higher HLA-DQ2 prevalence is reported in European population where wheat has been the staple food for thousands of years. In non-European population, this pattern of HLA-DQ CD-predisposing gene distribution has not always been found. The aim of this study was to evaluate the HLA-DQ2 and HLA-DQ8 distribution in the native low-gluten consuming southern Indian population. METHODS: Overall, 211 dried blood spots (DBS) were collected from native southern Indian individuals. HLA-DQ characterization and the determination of homozygous/heterozygous status were performed using commercially available HLA-DQ typing kits. RESULTS: Of 211 collected DBS, 88 (42%, 95% CI: 36-48) were positive for HLA-DQ2 and/or HLA-DQ8 heterodimers. Overall, 40 (19%, 95% CI: 14-24) samples typed positive for HLA-DQ2 and 48 (23%, 95% CI: 18-28) typed positive for HLA-DQ8 genotypes. Of 40 HLA-DQ2-positive individuals, only one subject tested homozygous for the DQB1*02 allele. CONCLUSIONS: In the southern Indian native general population, the prevalence of HLA-DQ8 is higher in comparison to HLA-DQ2 prevalence. This finding could be related to the delayed introduction of wheat in the diet of the southern Indian population.