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Doytchinova I, Atanasova M, Fernandez A, Moreno FJ, Koning F, Dimitrov I. Modeling Peptide-Protein Interactions by a Logo-Based Method: Application in Peptide-HLA Binding Predictions. Molecules 2024; 29:284. [PMID: 38257197 PMCID: PMC10818588 DOI: 10.3390/molecules29020284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 12/18/2023] [Accepted: 12/23/2023] [Indexed: 01/24/2024] Open
Abstract
Peptide-protein interactions form a cornerstone in molecular biology, governing cellular signaling, structure, and enzymatic activities in living organisms. Improving computational models and experimental techniques to describe and predict these interactions remains an ongoing area of research. Here, we present a computational method for peptide-protein interactions' description and prediction based on leveraged amino acid frequencies within specific binding cores. Utilizing normalized frequencies, we construct quantitative matrices (QMs), termed 'logo models' derived from sequence logos. The method was developed to predict peptide binding to HLA-DQ2.5 and HLA-DQ8.1 proteins associated with susceptibility to celiac disease. The models were validated by more than 17,000 peptides demonstrating their efficacy in discriminating between binding and non-binding peptides. The logo method could be applied to diverse peptide-protein interactions, offering a versatile tool for predictive analysis in molecular binding studies.
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Affiliation(s)
- Irini Doytchinova
- Faculty of Pharmacy, Medical University of Sofia, 1000 Sofia, Bulgaria; (M.A.); (I.D.)
| | - Mariyana Atanasova
- Faculty of Pharmacy, Medical University of Sofia, 1000 Sofia, Bulgaria; (M.A.); (I.D.)
| | | | - F. Javier Moreno
- Instituto de Investigación en Ciencias de la Alimentación (CIAL), CSIC-UAM, CEI (UAM+CSIC), Nicolás Cabrera, 9, 28049 Madrid, Spain;
| | - Frits Koning
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Centre, 2333 ZA Leiden, The Netherlands;
| | - Ivan Dimitrov
- Faculty of Pharmacy, Medical University of Sofia, 1000 Sofia, Bulgaria; (M.A.); (I.D.)
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Atanasova M, Dimitrov I, Fernandez A, Moreno J, Koning F, Doytchinova I. Assessment of Novel Proteins Triggering Celiac Disease via Docking-Based Approach. Molecules 2023; 29:138. [PMID: 38202724 PMCID: PMC10780262 DOI: 10.3390/molecules29010138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/22/2023] [Accepted: 12/24/2023] [Indexed: 01/12/2024] Open
Abstract
Human leukocyte antigens (HLAs) are pivotal in antigen processing, presenting to CD4+ T cells, and are linked to autoimmune disease susceptibility. In celiac disease, HLA-DQ2.5 and HLA-DQ8.1 bind gluten peptides on APCs, some recognized by CD4+ T cells, prompting inflammation and tissue damage. While extensively studied experimentally, these alleles lack comprehensive in silico analysis. To explore peptide-HLA preferences, we used molecular docking on peptide libraries, deriving quantitative matrices (QMs) for evaluating amino acids at nine-residue peptide binding cores. Our findings tie specific residue preferences to peptide backbone conformations. Validating QMs on known binders and non-binders showed strong predictive power (89-94% accuracy). These QMs excel in screening protein libraries, even whole proteomes, notably reducing time and costs for celiac disease risk assessment in novel proteins. This computational approach aligns with European Food Safety Authority guidance, promising efficient screening for potential celiac disease triggers.
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Affiliation(s)
- Mariyana Atanasova
- Faculty of Pharmacy, Medical University of Sofia, 1000 Sofia, Bulgaria; (I.D.); (I.D.)
| | - Ivan Dimitrov
- Faculty of Pharmacy, Medical University of Sofia, 1000 Sofia, Bulgaria; (I.D.); (I.D.)
| | | | - Javier Moreno
- Instituto de Investigación en Ciencias de la Alimentación (CIAL), Consejo Superior de Investigaciones Cientificas-Universidad Autonoma de Madrid (CSIC-UAM), Campus of Interntional Excellence—CEI (UAM+CSIC), Nicolás Cabrera, 9, 28049 Madrid, Spain;
| | - Frits Koning
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Centre, 2333 ZA Leiden, The Netherlands;
| | - Irini Doytchinova
- Faculty of Pharmacy, Medical University of Sofia, 1000 Sofia, Bulgaria; (I.D.); (I.D.)
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Oliveira LC, Dornelles AC, Nisihara RM, Bruginski ERD, Santos PID, Cipolla GA, Boschmann SE, Messias-Reason IJD, Campos FR, Petzl-Erler ML, Boldt ABW. The Second Highest Prevalence of Celiac Disease Worldwide: Genetic and Metabolic Insights in Southern Brazilian Mennonites. Genes (Basel) 2023; 14:genes14051026. [PMID: 37239386 DOI: 10.3390/genes14051026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 04/26/2023] [Accepted: 04/27/2023] [Indexed: 05/28/2023] Open
Abstract
Celiac disease (CD), despite its high morbidity, is an often-underdiagnosed autoimmune enteropathy. Using a modified version of the Brazilian questionnaire of the 2013 National Health Survey, we interviewed 604 Mennonites of Frisian/Flemish origin that have been isolated for 25 generations. A subgroup of 576 participants were screened for IgA autoantibodies in serum, and 391 participants were screened for HLA-DQ2.5/DQ8 subtypes. CD seroprevalence was 1:29 (3.48%, 95% CI = 2.16-5.27%) and biopsy-confirmed CD was 1:75 (1.32%, 95% CI = 0.57-2.59%), which is superior to the highest reported global prevalence (1:100). Half (10/21) of the patients did not suspect the disease. HLA-DQ2.5/DQ8 increased CD susceptibility (OR = 12.13 [95% CI = 1.56-94.20], p = 0.003). The HLA-DQ2.5 carrier frequency was higher in Mennonites than in Brazilians (p = 7 × 10-6). HLA-DQ8 but not HLA-DQ2.5 carrier frequency differed among settlements (p = 0.007) and was higher than in Belgians, a Mennonite ancestral population (p = 1.8 × 10-6), and higher than in Euro-Brazilians (p = 6.5 × 10-6). The glutathione pathway, which prevents reactive oxygen species-causing bowel damage, was altered within the metabolic profiles of untreated CD patients. Those with lower serological positivity clustered with controls presenting close relatives with CD or rheumatoid arthritis. In conclusion, Mennonites have a high CD prevalence with a strong genetic component and altered glutathione metabolism that calls for urgent action to alleviate the burden of comorbidities due to late diagnosis.
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Affiliation(s)
- Luana Caroline Oliveira
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
- Postgraduate Program in Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
| | - Amanda Coelho Dornelles
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
| | - Renato Mitsunori Nisihara
- Laboratory of Molecular Immunopathology, Department of Clinical Pathology, Clinical Hospital, Federal University of Paraná (UFPR), Rua General Carneiro, 181 Prédio Central, 11° Andar, Alto da Glória, Curitiba 80060-240, Paraná, Brazil
| | - Estevan Rafael Dutra Bruginski
- Postgraduate Program in Pharmaceutical Sciences, Laboratory of Bioscience and Mass Spectrometry, Department of Pharmacy, Federal University of Paraná (UFPR), Av. Pref. Lothário Meissner, 632, Jardim Botânico, Curitiba 80210-170, Paraná, Brazil
| | - Priscila Ianzen Dos Santos
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
- Postgraduate Program in Internal Medicine, Federal University of Paraná (UFPR), Rua General Carneiro, 181 Prédio Central, 11° Andar, Alto da Glória, Curitiba 80060-240, Paraná, Brazil
| | - Gabriel Adelman Cipolla
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
- Postgraduate Program in Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
| | - Stefanie Epp Boschmann
- Laboratory of Molecular Immunopathology, Department of Clinical Pathology, Clinical Hospital, Federal University of Paraná (UFPR), Rua General Carneiro, 181 Prédio Central, 11° Andar, Alto da Glória, Curitiba 80060-240, Paraná, Brazil
- Postgraduate Program in Internal Medicine, Federal University of Paraná (UFPR), Rua General Carneiro, 181 Prédio Central, 11° Andar, Alto da Glória, Curitiba 80060-240, Paraná, Brazil
| | - Iara José de Messias-Reason
- Laboratory of Molecular Immunopathology, Department of Clinical Pathology, Clinical Hospital, Federal University of Paraná (UFPR), Rua General Carneiro, 181 Prédio Central, 11° Andar, Alto da Glória, Curitiba 80060-240, Paraná, Brazil
- Postgraduate Program in Internal Medicine, Federal University of Paraná (UFPR), Rua General Carneiro, 181 Prédio Central, 11° Andar, Alto da Glória, Curitiba 80060-240, Paraná, Brazil
| | - Francinete Ramos Campos
- Postgraduate Program in Pharmaceutical Sciences, Laboratory of Bioscience and Mass Spectrometry, Department of Pharmacy, Federal University of Paraná (UFPR), Av. Pref. Lothário Meissner, 632, Jardim Botânico, Curitiba 80210-170, Paraná, Brazil
| | - Maria Luiza Petzl-Erler
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
- Postgraduate Program in Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
| | - Angelica Beate Winter Boldt
- Laboratory of Human Molecular Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
- Postgraduate Program in Genetics, Department of Genetics, Federal University of Paraná (UFPR), Centro Politécnico, Jardim das Américas, Curitiba 81531-990, Paraná, Brazil
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Lindstad CB, Qiao SW, Johannesen MK, Fugger L, Sollid LM, du Pré MF. Characterization of T-cell receptor transgenic mice recognizing immunodominant HLA-DQ2.5-restricted gluten epitopes. Eur J Immunol 2020; 51:1002-1005. [PMID: 33368209 DOI: 10.1002/eji.202048859] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/02/2020] [Accepted: 11/27/2020] [Indexed: 11/06/2022]
Abstract
We created a TCR transgenic mouse with CD4+ T cells recognizing the immunodominant DQ2.5-glia-ω2 gluten epitope. We show that these cells respond to deamidated gluten feed in vivo and compare them to previously published α2- and γ1-specific mice. These mice may help enlighten key aspects of celiac disease pathogenesis.
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Affiliation(s)
- Christian B Lindstad
- K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway.,Department of Immunology, University of Oslo, Oslo, Norway
| | - Shuo-Wang Qiao
- K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway.,Department of Immunology, University of Oslo, Oslo, Norway
| | - Marie K Johannesen
- K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway.,Department of Immunology, University of Oslo, Oslo, Norway
| | - Lars Fugger
- Oxford Centre for Neuroinflammation, Nuffield Department of Clinical Neurosciences, Division of Clinical Neurology and Medical Research Council Human Immunology Unit, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Ludvig M Sollid
- K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway.,Department of Immunology, University of Oslo, Oslo, Norway.,Department of Immunology, Oslo University Hospital, Oslo, Norway
| | - M Fleur du Pré
- K.G. Jebsen Coeliac Disease Research Centre, University of Oslo, Oslo, Norway.,Department of Immunology, Oslo University Hospital, Oslo, Norway
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Airaksinen L, Laurikka P, Huhtala H, Kurppa K, Salmi T, Saavalainen P, Kaukinen K, Lindfors K. Influence of HLA-DQ2.5 Dose on Clinical Picture of Unrelated Celiac Disease Patients. Nutrients 2020; 12:nu12123775. [PMID: 33317091 PMCID: PMC7764246 DOI: 10.3390/nu12123775] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 12/07/2020] [Indexed: 12/13/2022] Open
Abstract
The clinical phenotype of celiac disease varies considerably among patients and the dosage of HLA-DQ2.5 alleles has been suggested to be a contributing factor. We investigated whether HLA-DQ2.5 allele dosage is associated with distinct clinical parameters at the time of diagnosis and with patients’ response to a gluten-free diet. The final cohort included 605 carefully phenotyped non-related Finnish celiac disease patients grouped as having 0, 1 or 2 copies of HLA-DQ2.5. Clinical data at the time of diagnosis and during gluten-free diet were collected systematically from medical records and supplementary interviews. An increasing HLA-DQ2.5 dose effect was detected for celiac disease antibody positivity at diagnosis (p = 0.021) and for the presence of any first-degree relatives with celiac disease (p = 0.011 and p = 0.031, respectively). Instead, DQ2.5-negative patients were suffering most often from classical symptoms at diagnosis (p = 0.007 between HLA groups). In addition, during follow-up they were most often symptomatic despite a gluten-free diet (p = 0.002 between groups). Our results thus suggest that increasing HLA-DQ2.5 dose only has a minor effect on the clinical picture of celiac disease. However, HLA-DQ2.5-negative patients should not be overlooked in clinical practice and particular attention should be paid to this patient group during gluten-free diet.
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Affiliation(s)
- Laura Airaksinen
- Celiac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, 33520 Tampere, Finland; (L.A.); (P.L.); (T.S.); (K.K.)
| | - Pilvi Laurikka
- Celiac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, 33520 Tampere, Finland; (L.A.); (P.L.); (T.S.); (K.K.)
| | - Heini Huhtala
- Faculty of Social Sciences, Tampere University, 33520 Tampere, Finland;
| | - Kalle Kurppa
- Tampere Centre for Child Health Research, Tampere University Hospital and Tampere University, 33521 Tampere, Finland;
- Department of Pediatrics, Seinäjoki Central Hospital and University Consortium of Seinäjoki, 60220 Seinäjoki, Finland
| | - Teea Salmi
- Celiac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, 33520 Tampere, Finland; (L.A.); (P.L.); (T.S.); (K.K.)
- Department of Dermatology, Tampere University Hospital, 33521 Tampere, Finland
| | - Päivi Saavalainen
- Research Programs Unit, Immunobiology, and Haartman Institute, Department of Medical Genetics, University of Helsinki, 00014 Helsinki, Finland;
| | - Katri Kaukinen
- Celiac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, 33520 Tampere, Finland; (L.A.); (P.L.); (T.S.); (K.K.)
- Department of Internal Medicine, Tampere University Hospital, 33521 Tampere, Finland
| | - Katri Lindfors
- Celiac Disease Research Center, Faculty of Medicine and Health Technology, Tampere University, 33520 Tampere, Finland; (L.A.); (P.L.); (T.S.); (K.K.)
- Correspondence:
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Al-Hussaini A, Eltayeb-Elsheikh N, Alharthi H, Osman A, Alshahrani M, Sandogji I, Alrashidi S, Bashir MS. HLA-DQ genotypes relative risks for celiac disease in Arabs: A case-control study. J Dig Dis 2019; 20:602-608. [PMID: 31496112 DOI: 10.1111/1751-2980.12817] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 08/30/2019] [Accepted: 09/04/2019] [Indexed: 12/11/2022]
Abstract
OBJECTIVES It remains unknown what degree of risk is conferred by celiac disease (CD)-predisposing human leukocyte antigen (HLA)-DQ genotypes in Saudi Arabia compared with in Western countries. In this study, we aimed to determine the CD risk gradient associated with the HLA-DQ genotypes and to compare HLA-DQ genotypes between symptomatic patients with CD and screening-identified asymptomatic CD patients. METHODS We enrolled three groups of subjects, including 46 CD children diagnosed consecutively over the past 10 years, 54 CD children diagnosed during a mass screening of schoolchildren, and 192 healthy controls. All the participants were typed for the HLA-DQA1 and HLA-DQB1 genes by polymerase chain reaction sequence-specific oligonucleotide probes. RESULTS Comparing the patients with CD to controls, we identified 5 groups in the CD risk gradient: (i) very high risk associated with the DQ2.5/DQ8 genotype (odds ratio [OR] 46.93); (ii) high risk (homozygous DQ2.5, DQ2.5/DQ2.2; OR 4.12-5.04); (iii) intermediate risk (heterozygous DQ2.5, DQ8/DQ2.2; OR 1.61 and 1.67); (iv) low risk (DQ8, DQ2.2); and (v) very low risk (DQ2.x, DQX.5, DQX.x). Heterozygous DQ8 was more common in screening-identified group compared to symptomatic patients (13.0% vs 2.2%); however, other genotypes were very similar between the two groups. CONCLUSION The highest risk of developing CD in our Saudi Arabia population is associated with the DQ2.5/DQ8 genotype.
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Affiliation(s)
- Abdulrahman Al-Hussaini
- Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City, Riyadh, Saudi Arabia.,College of Medicine, Alfaisal University, Riyadh, Saudi Arabia
| | - Nezar Eltayeb-Elsheikh
- Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Hanan Alharthi
- Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Awad Osman
- Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Maram Alshahrani
- Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Ibrahim Sandogji
- Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Sami Alrashidi
- Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City, Riyadh, Saudi Arabia
| | - Muhammed Salman Bashir
- Department of Biostatistics, Research Services Administration, Research Center at King Fahad Medical City, Riyadh, Saudi Arabia
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Cabrera CM, Sánchez-Godoy L, Navas-López VM. Is the double gene dose of DQ2.5 or DQ2.5/DQ2.2 an involved factor in the clinical features of celiac disease? Scand J Gastroenterol 2019; 54:960-964. [PMID: 31361165 DOI: 10.1080/00365521.2019.1647283] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Objectives: Celiac disease (CD) is barely known if the quantitative effect of DQB1*02 (DQ2) double dose in antigen presentation to T-cells has translation into the clinic. For this, we have conducted a case-control study in a cohort of two hundred and nineteen patients with CD. Material and methods: For the control group, individuals were enrolled with single dose of DQ2, carrying DQ2.5 heterodimers in heterozygous state (n = 109). The cases with CD were diving into three groups: cases with overall DQ2 double dose (n = 110), DQ2.5 homozygous (n = 33) and DQ2.5/DQ2.2 heterozygous (n = 77). Prevalence and associations of demographic, laboratory, histological and clinical characteristics between the control group and cases were studied. Results: No differences were found for the total of 16 variables analyzed between the control group and overall DQ2 double dose as well as DQ2.5 homozygous cases. In contrast to DQ2.5/DQ2.2, heterozygous cases presented a protection factor for developing allergy to airway allergens regarding the control group (OR = 0.210, p = .019). Conclusions: To date, this negative association has not been described. Further studies will be necessary to elucidate the implication of this protection factor in CD. Since, until now the association between CD and allergic diseases has been poorly studied.
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Affiliation(s)
- Carmen M Cabrera
- Immunology Section, Department of Hematology, Carlos Haya Regional University Hospital , Málaga , Spain
| | - Lorenzo Sánchez-Godoy
- Clinical Laboratory Service, Carlos Haya Regional University Hospital , Málaga , Spain
| | - Víctor M Navas-López
- Pediatric Gastroenterology and Nutrition Unit, Carlos Haya Regional University Hospital , Málaga , Spain
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Abstract
BACKGROUND/AIM To determine the frequency of celiac disease (CD)-predisposing human leukocyte antigen (HLA)-DQ genotypes in the Saudi population, where the prevalence of CD is 1.5% as recently reported in a mass screening study. PATIENTS AND METHODS In a cross-sectional population-based study, a total of 192 randomly selected healthy school children (97 females, mean age 10.5 ± 2.2 years, all negative for tissue transglutaminase-IgA) were typed for D QA1 and D QB1 genes by polymerase chain reaction sequence-specific oligonucleotide probes. RESULTS Of the 192 children, 52.7% carried the high-risk CD-associated HLA-DQ molecules: homozygous DQ2.5 ( 2.6%), DQ2.5/DQ2.2 ( 4.7%), heterozygous DQ2.5 ( 28.15%), homozygous DQ8 ( 4.2%), DQ8/DQ2.2 ( 3.6%), and double dose DQ2.2 ( 9.4%). Low-risk CD-associated HLA-DQ molecules (single dose DQ2.2 and heterozygous DQ8) constituted 3.6% and 9.4%, respectively. Among the very low-risk groups, individuals lacking alleles that contribute to DQ2/DQ8 variants (33.5%), 13.5% carried only one of the alleles of the high-risk HLA-DQ2.5 heterodimer called "half-heterodimer" (HLA-DQA1*05 in 12% and HLA-DQB1* 02 in 1.5%), and 20.8% lacked all the susceptible alleles (DQX.x). Gender distribution was not significantly different among the CD-risk groups. CONCLUSION We report one of the highest frequencies of CD-predisposing HLA-DQ genotypes among healthy general populations (52.7%) worldwide, which might partly explain the high prevalence of CD in the Saudi community.
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Affiliation(s)
- Abdulrahman Al-Hussaini
- Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia,College of Medicine, Alfaisal University, Riyadh, Kingdom of Saudi Arabia,Prince Abdullah bin Khalid Celiac Disease Research Chair, Department of Pediatrics, Faculty of Medicine, King Saud University, Riyadh, Kingdom of Saudi Arabia,Address for correspondence: Dr. Abdulrahman Al-Hussaini, Division of Pediatric Gastroenterology, Children's Specialized Hospital, King Fahad Medical City, College of Medicine, Alfaisal University, Riyadh, Kingdom of Saudi Arabia. E-mail:
| | - Hanan Alharthi
- Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Awad Osman
- Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Nezar Eltayeb-Elsheikh
- Department of Pathology and Laboratory Medicine, Division of Immunology, King Fahad Medical City, Riyadh, Kingdom of Saudi Arabia
| | - Aziz Chentoufi
- Department of Immunology, University of Mohammed VI for health sciences, Casablanca, Morocco
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