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Machraoui S, Errafii K, Oujamaa I, Belghali MY, Hakmaoui A, Lamjadli S, Eddehbi FE, Brahim I, Haida Y, Admou B. Frequency of the Main Human Leukocyte Antigen A, B, DR, and DQ Loci Known to Be Associated with the Clearance or Persistence of Hepatitis C Virus Infection in a Healthy Population from the Southern Region of Morocco: A Preliminary Study. Diseases 2024; 12:106. [PMID: 38785761 PMCID: PMC11120154 DOI: 10.3390/diseases12050106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 02/28/2024] [Accepted: 03/05/2024] [Indexed: 05/25/2024] Open
Abstract
Hepatitis C Virus (HCV) infection represents a significant global health challenge, with its natural course largely influenced by the host's immune response. Human Leukocyte Antigen (HLA) molecules, particularly HLA class I and II, play a crucial role in the adaptive immune response against HCV. The polymorphism of HLA molecules contributes to the variability in immune response, affecting the outcomes of HCV infection. This study aims to investigate the frequency of HLA A, B, DR, and DQ alleles known to be associated with HCV clearance or persistence in a healthy Moroccan population. Conducted at the University Hospital Center Mohammed VI, Marrakech, this study spanned from 2015 to 2022 and included 703 healthy Moroccan individuals. HLA class I and II typing was performed using complement-dependent cytotoxicity and polymerase chain reaction-based methodologies. The results revealed the distinct patterns of HLA-A, B, DRB1, and DQB1 alleles in the Moroccan population. Notably, alleles linked to favorable HCV outcomes, such as HLA-DQB1*0301, DQB1*0501, and DRB1*1101, were more prevalent. Conversely, alleles associated with increased HCV susceptibility and persistence, such as HLA-DQB1*02 and DRB1*03, were also prominent. Gender-specific variations in allele frequencies were observed, providing insights into genetic influences on HCV infection outcomes. The findings align with global trends in HLA allele associations with HCV infection outcomes. The study emphasizes the role of host genetics in HCV infection, highlighting the need for further research in the Moroccan community, including HCV-infected individuals. The prevalence of certain HLA alleles, both protective and susceptibility-linked, underscores the potential for a national HLA data bank in Morocco.
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Affiliation(s)
- Safa Machraoui
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
- Biosciences Research Laboratory, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech 40080, Morocco
- African Genome Center, Mohammed VI Polytechnic University (UM6P), Ben Guerir 43151, Morocco;
| | - Khaoula Errafii
- African Genome Center, Mohammed VI Polytechnic University (UM6P), Ben Guerir 43151, Morocco;
| | - Ider Oujamaa
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
| | - Moulay Yassine Belghali
- Department of Biology, Faculty of Sciences Dhar El Mahraz, Sidi Mohammed Ben Abdellah University, Fez 30003, Morocco;
| | - Abdelmalek Hakmaoui
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
| | - Saad Lamjadli
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
| | - Fatima Ezzohra Eddehbi
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
| | - Ikram Brahim
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
| | - Yasmine Haida
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
| | - Brahim Admou
- Laboratory of Immunology and HLA, Center of Clinical Research, Mohammed VI University Hospital, Marrakech 40080, Morocco; (I.O.); (A.H.); (S.L.); (F.E.E.); (I.B.); (Y.H.); (B.A.)
- Biosciences Research Laboratory, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech 40080, Morocco
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Yu SC, Lin ME. Kikuchi disease in acute leukaemia: a distinct clinical syndrome with HLA association. Histopathology 2024; 84:1003-1012. [PMID: 38275182 DOI: 10.1111/his.15145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 12/23/2023] [Accepted: 01/06/2024] [Indexed: 01/27/2024]
Abstract
AIMS To report the clinicopathological features of Kikuchi disease in patients with acute leukaemia, emphasising similarities among cases. METHODS AND RESULTS In a cohort of 454 Kikuchi disease patients, we identified three cases of concurrent acute leukaemia. These patients shared similar clinical traits, with Kikuchi disease emerging approximately a month after induction chemotherapy onset, featuring neck-region lymphadenopathy. Notably, two patients were middle-aged, deviating from the typical age distribution of Kikuchi disease. Histologically, these cases aligned with typical Kikuchi disease. Negative immunohistochemical stains (CD34, CD117, ERG, TdT) indicated the absence of extramedullary leukaemic infiltration. Herpes simplex virus immunohistochemical staining was also negative. Significantly, a human leucocyte antigen (HLA) association was observed in these three cases. HLA-B*15:01, C*04:01, and DRB1*04:06 were more prevalent in these patients compared to the general population (compared with three independent control cohorts: Taiwanese Han Chinese (n = 504), Tzu Chi Taiwanese bone marrow donors (n = 364) and Hong Kong Chinese (n = 5266)). CONCLUSIONS Our study underscores the unique link between Kikuchi disease and acute leukaemia, characterised by specific features and HLA associations. This underlines Kikuchi disease as a possible differential diagnosis in pertinent clinical scenarios. Furthermore, this syndrome offers insights into postchemotherapy immunology in acute leukaemia, enhancing comprehension.
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Affiliation(s)
- Shan-Chi Yu
- Department of Pathology and Graduate Institute of Pathology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Department of Pathology, National Taiwan University Hospital, Taipei, Taiwan
| | - Ming-En Lin
- Division of Hematology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
- Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
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Slieker RC, Warmerdam DO, Vermeer MH, van Doorn R, Heemskerk MHM, Scheeren FA. Reassessing human MHC-I genetic diversity in T cell studies. Sci Rep 2024; 14:7966. [PMID: 38575727 PMCID: PMC10995142 DOI: 10.1038/s41598-024-58777-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 04/03/2024] [Indexed: 04/06/2024] Open
Abstract
The Major Histocompatibility Complex class I (MHC-I) system plays a vital role in immune responses by presenting antigens to T cells. Allele specific technologies, including recombinant MHC-I technologies, have been extensively used in T cell analyses for COVID-19 patients and are currently used in the development of immunotherapies for cancer. However, the immense diversity of MHC-I alleles presents challenges. The genetic diversity serves as the foundation of personalized medicine, yet it also poses a potential risk of exacerbating healthcare disparities based on MHC-I alleles. To assess potential biases, we analysed (pre)clinical publications focusing on COVID-19 studies and T cell receptor (TCR)-based clinical trials. Our findings reveal an underrepresentation of MHC-I alleles associated with Asian, Australian, and African descent. Ensuring diverse representation is vital for advancing personalized medicine and global healthcare equity, transcending genetic diversity. Addressing this disparity is essential to unlock the full potential of T cells for enhancing diagnosis and treatment across all individuals.
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Affiliation(s)
- Roderick C Slieker
- Department of Cell and Chemical Biology, Leiden University Medical Center, Leiden, The Netherlands
- Leiden Center for Computational Oncology, Leiden University Medical Center, Leiden, The Netherlands
| | - Daniël O Warmerdam
- Centre for Future Affordable & Sustainable Therapy Development (FAST), The Hague, The Netherlands
| | - Maarten H Vermeer
- Department of Dermatology, Leiden University Medical Center, Leiden, The Netherlands
| | - Remco van Doorn
- Department of Dermatology, Leiden University Medical Center, Leiden, The Netherlands
- Department of Dermatology, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Mirjam H M Heemskerk
- Department of Hematology, Leiden University Medical Center, Leiden, The Netherlands
| | - Ferenc A Scheeren
- Department of Dermatology, Leiden University Medical Center, Leiden, The Netherlands.
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Yin R, Melton S, Huseby ES, Kardar M, Chakraborty AK. How persistent infection overcomes peripheral tolerance mechanisms to cause T cell-mediated autoimmune disease. Proc Natl Acad Sci U S A 2024; 121:e2318599121. [PMID: 38446856 PMCID: PMC10945823 DOI: 10.1073/pnas.2318599121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Accepted: 02/06/2024] [Indexed: 03/08/2024] Open
Abstract
T cells help orchestrate immune responses to pathogens, and their aberrant regulation can trigger autoimmunity. Recent studies highlight that a threshold number of T cells (a quorum) must be activated in a tissue to mount a functional immune response. These collective effects allow the T cell repertoire to respond to pathogens while suppressing autoimmunity due to circulating autoreactive T cells. Our computational studies show that increasing numbers of pathogenic peptides targeted by T cells during persistent or severe viral infections increase the probability of activating T cells that are weakly reactive to self-antigens (molecular mimicry). These T cells are easily re-activated by the self-antigens and contribute to exceeding the quorum threshold required to mount autoimmune responses. Rare peptides that activate many T cells are sampled more readily during severe/persistent infections than in acute infections, which amplifies these effects. Experiments in mice to test predictions from these mechanistic insights are suggested.
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Affiliation(s)
- Rose Yin
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Samuel Melton
- Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Eric S. Huseby
- Basic Pathology, Department of Pathology, University of Massachusetts Medical School, Worcester, MA01655
| | - Mehran Kardar
- Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA02139
| | - Arup K. Chakraborty
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA02139
- Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA02139
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA02139
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA02139
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Marzouka NAD, Alnaqbi H, Al-Aamri A, Tay G, Alsafar H. Investigating the genetic makeup of the major histocompatibility complex (MHC) in the United Arab Emirates population through next-generation sequencing. Sci Rep 2024; 14:3392. [PMID: 38337023 PMCID: PMC10858242 DOI: 10.1038/s41598-024-53986-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Accepted: 02/07/2024] [Indexed: 02/12/2024] Open
Abstract
The Human leukocyte antigen (HLA) molecules are central to immune response and have associations with the phenotypes of various diseases and induced drug toxicity. Further, the role of HLA molecules in presenting antigens significantly affects the transplantation outcome. The objective of this study was to examine the extent of the diversity of HLA alleles in the population of the United Arab Emirates (UAE) using Next-Generation Sequencing methodologies and encompassing a larger cohort of individuals. A cohort of 570 unrelated healthy citizens of the UAE volunteered to provide samples for Whole Genome Sequencing and Whole Exome Sequencing. The definition of the HLA alleles was achieved through the application of the bioinformatics tools, HLA-LA and xHLA. Subsequently, the findings from this study were compared with other local and international datasets. A broad range of HLA alleles in the UAE population, of which some were previously unreported, was identified. A comparison with other populations confirmed the current population's unique intertwined genetic heritage while highlighting similarities with populations from the Middle East region. Some disease-associated HLA alleles were detected at a frequency of > 5%, such as HLA-B*51:01, HLA-DRB1*03:01, HLA-DRB1*15:01, and HLA-DQB1*02:01. The increase in allele homozygosity, especially for HLA class I genes, was identified in samples with a higher level of genome-wide homozygosity. This highlights a possible effect of consanguinity on the HLA homozygosity. The HLA allele distribution in the UAE population showcases a unique profile, underscoring the need for tailored databases for traditional activities such as unrelated transplant matching and for newer initiatives in precision medicine based on specific populations. This research is part of a concerted effort to improve the knowledge base, particularly in the fields of transplant medicine and investigating disease associations as well as in understanding human migration patterns within the Arabian Peninsula and surrounding regions.
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Affiliation(s)
- Nour Al Dain Marzouka
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Halima Alnaqbi
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Amira Al-Aamri
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates
| | - Guan Tay
- Division of Psychiatry, Faculty of Health and Medical Sciences, Medical School, The University of Western Australia, Crawley, WA, Australia
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia
| | - Habiba Alsafar
- Center for Biotechnology, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates.
- College of Medicine and Health Sciences, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates.
- Department of Biomedical Engineering, Khalifa University of Science and Technology, Abu Dhabi, United Arab Emirates.
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Rollin FG, Abaza S. The Careful Use of Racial Categories in Genetic Studies of Liver Injury. Am J Gastroenterol 2024; 119:391-392. [PMID: 38305249 DOI: 10.14309/ajg.0000000000002513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Affiliation(s)
- Francois G Rollin
- Department of Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Suhaib Abaza
- Department of Emergency Medicine, Emory University School of Medicine, Atlanta, Georgia, USA
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Elston DM. Letter from the Editor: Ensuring appropriate diversity in clinical trials. J Am Acad Dermatol 2024:S0190-9622(23)03397-2. [PMID: 38185253 DOI: 10.1016/j.jaad.2023.12.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 12/21/2023] [Indexed: 01/09/2024]
Affiliation(s)
- Dirk M Elston
- Department of Dermatology and Dermatologic Surgery Medical University of South California, Charleston, South Carolina.
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Shiina T, Kulski JK. HLA Genetics for the Human Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1444:237-258. [PMID: 38467984 DOI: 10.1007/978-981-99-9781-7_16] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Highly polymorphic human leukocyte antigen (HLA) molecules (alleles) expressed by different classical HLA class I and class II genes have crucial roles in the regulation of innate and adaptive immune responses, transplant rejection and in the pathogenesis of numerous infectious and autoimmune diseases. To date, over 35,000 HLA alleles have been published from the IPD-IMGT/HLA database, and specific HLA alleles and HLA haplotypes have been reported to be associated with more than 100 different diseases and phenotypes. Next generation sequencing (NGS) technology developed in recent years has provided breakthroughs in various HLA genomic/gene studies and transplant medicine. In this chapter, we review the current information on the HLA genomic structure and polymorphisms, as well as the genetic context in which numerous disease associations have been identified in this region.
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Affiliation(s)
| | - Jerzy K Kulski
- Tokai University School of Medicine, Isehara, Japan
- School of Biomedical Sciences, The University of Western Australia, Nedlands, Western Australia, Australia
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Espada E, Ligeiro D, Trindade H, Lacerda JF. HLA frequency distribution of the Portuguese bone marrow donor registry. Front Immunol 2023; 14:1286001. [PMID: 38149254 PMCID: PMC10749969 DOI: 10.3389/fimmu.2023.1286001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/22/2023] [Indexed: 12/28/2023] Open
Abstract
Introduction The Portuguese donor Registry of CEDACE was the fifth largest per capita bone marrow donor Registry of the WMDA as of 2019 and has yet to be thoroughly analyzed. We aimed to characterize its various aspects, including demographics and HLA allele and haplotype frequencies, to evaluate the genetic matching propensity score and ultimately further develop it. Methods We described and compared characteristics of the donor population with census data and used an Expectation-Maximization algorithm and analyses of molecular variance to assess haplotype frequencies and establish phylogenetic distances between regions and districts within the country. Results We identified 396545 donors, corresponding to 3.85% of the Portuguese population; the median donor age was 39 years, with 60.4% of female donors. Most donors were Portuguese nationals, although 40 other nationalities were present, with a significant proportion of donors from Brazil and Portuguese-speaking African Countries; almost all donors self-reported as Western, with the second largest group reporting African ancestry. There was an asymmetric contribution of donors from different districts and regions, with most coming from coastal districts and few from the southern districts and autonomous regions; foreign and self-declared non-Western donors were mainly located in the Metropolitan Area of Lisbon and the South. Although most donors were typed in three loci (HLA-A, HLA-B and HLA-DRB1), only 44% were also typed in HLA-C, 1.28% in HLA-DQB1 and only 0.77% in all five loci and in high-resolution. There were varying allele and haplotype frequencies across districts and regions, with the most common three loci, low-resolution haplotypes, being HLA-A*01~B*08~DRB1*03, A*29~B*44~DRB1*07 and HLA-A*02~B*44~DRB1*04; some haplotypes were more prevalent in the South, others in the North and a few in the autonomous regions; African and foreign donors presented relevant differences in haplotype frequency distributions, including rare haplotypes of potential interest. We also report on four loci, low-resolution frequency distributions. Using AMOVA, we compared genetic distances between districts and regions, which recapitulated the country's geography. Discussion Our analysis showed potential paths to optimization of the Registry, including increasing the male donor pool and focusing on underrepresented districts and particular populations of interest, such as donors from Portuguese-speaking African countries.
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Affiliation(s)
- Eduardo Espada
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Serviço de Hematologia e Transplantação de Medula, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte, EPE, Lisbon, Portugal
| | - Dário Ligeiro
- Centro de Sangue e Transplantação de Lisboa, Instituto Português do Sangue e da Transplantação, IP, Lisbon, Portugal
- Immunosurgery Unit, Centro Clínico Champalimaud, Lisbon, Portugal
| | - Hélder Trindade
- Centro de Sangue e Transplantação de Lisboa, Instituto Português do Sangue e da Transplantação, IP, Lisbon, Portugal
| | - João F. Lacerda
- Instituto de Medicina Molecular João Lobo Antunes, Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal
- Serviço de Hematologia e Transplantação de Medula, Hospital de Santa Maria, Centro Hospitalar Universitário de Lisboa Norte, EPE, Lisbon, Portugal
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Al-Mendalawi MD. A call to establish HLA registry in Iraq. J Taibah Univ Med Sci 2023; 18:1507-1508. [PMID: 37693818 PMCID: PMC10482738 DOI: 10.1016/j.jtumed.2023.07.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 07/22/2023] [Indexed: 09/12/2023] Open
Affiliation(s)
- Mahmood D. Al-Mendalawi
- Pediatrics and Child Health, Consultant Paediatrician, Department of Paediatrics, Al-Kindy College of Medicine, University of Baghdad, Baghdad, Iraq
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Mrazek F. Population genetics and external proficiency testing for HLA disease associations. Front Genet 2023; 14:1268705. [PMID: 37937194 PMCID: PMC10626483 DOI: 10.3389/fgene.2023.1268705] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Accepted: 10/12/2023] [Indexed: 11/09/2023] Open
Abstract
Numerous associations of HLA variants with susceptibility to diseases, namely, those with an immunopathological component, have been described to date. The strongest HLA associations were incorporated into the standard algorithms for the diagnostics. Disease-associated HLA variants are routinely detected by various techniques including DNA-based assays. For the identification of HLA markers or their combinations with the highest diagnostic value and those with frequent clinical indications (e.g., HLA-B*27, -B*57:01, -DQ2/-DQ8, -DQB1*06:02), diagnostic tests that focus on a single or limited number of specific HLA antigens/alleles, have already been developed; the use of complete typing for particular HLA loci is a relevant alternative. Importantly, external proficiency testing (EPT) became an integral part of good laboratory practice for HLA disease associations in accredited laboratories and not only supports correct "technical" identification of the associated HLA variants, but also adequate interpretation of the results to the clinicians. In the present article selected aspects of EPT for HLA disease associations related to population genetics are reviewed and discussed with the emphasis on the optimal level of HLA typing resolution, population-based differences in disease associated HLA alleles within the allelic group, distribution and linkage disequilibrium of HLA alleles in particular populations and interpretation of the presence of less common HLA variants/haplotypes. In conclusion, the laboratories that perform and interpret the tests to the clinicians, producers of the certified diagnostics and EPT providers should consider, among others, the genetic characteristics of the populations in order to optimise the diagnostic value of the tests for disease-associated HLA variants.
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Affiliation(s)
- Frantisek Mrazek
- HLA laboratory, Department of Immunology, University Hospital, Olomouc, Czechia
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