{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,6]],"date-time":"2026-11-06T19:51:11Z","timestamp":1793994671127,"version":"4.8.0"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,6,22]],"date-time":"2023-06-22T00:00:00Z","timestamp":1687392000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:p>The aim of this study was to determine the Human Leukocyte Antigen (HLA) class II (<jats:italic>DRB1<\/jats:italic> and <jats:italic>DQB1<\/jats:italic>) alleles and haplotype frequency in Rheumatoid Arthritis <jats:bold>(<\/jats:bold>RA) in the Sudanese population. The frequency of <jats:italic>HLA-DRB1<\/jats:italic> and -<jats:italic>DQB1<\/jats:italic> alleles and <jats:italic>DRB1-DQB1<\/jats:italic> haplotypes were determined in 122 RA patients and 100 controls. HLA alleles were genotyped by the polymerase chain reaction-sequence specific primers (PCR-SSP) method. In RA patients, <jats:italic>HLA-DRB1*04 and *10<\/jats:italic> alleles were high in frequency (9.6% vs 14.2%, <jats:italic>P<\/jats:italic> = 0.038 and <jats:italic>P<\/jats:italic> = 0.042, respectively), and dependently on anti-citrullinated protein antibodies (ACPAs) seropositivity (<jats:italic>P<\/jats:italic> = 0.044 and <jats:italic>P<\/jats:italic> = 0.027, respectively). In contrast, the frequency of the <jats:italic>HLA-DRB1*07<\/jats:italic> allele was significantly low in patients than in controls (11.7% vs 5.0%, <jats:italic>P<\/jats:italic> = 0.010). Moreover, the <jats:italic>HLA-DQB1*03<\/jats:italic> allele was strongly associated with RA risk (42.2%, <jats:italic>P<\/jats:italic> = 2.2x10<jats:sup>-8<\/jats:sup>), whereas, <jats:italic>HLA-DQB1*02<\/jats:italic> and <jats:italic>*06<\/jats:italic> showed protective effects against RA (23.1% and 42.2%, <jats:italic>P<\/jats:italic> = 0.024 and <jats:italic>P<\/jats:italic> = 2.2x10<jats:sup>-6<\/jats:sup>, respectively). Five different HLA haplotypes, <jats:italic>DRB1*03-DQB1*03<\/jats:italic> (<jats:italic>P<\/jats:italic> = 0.00003), <jats:italic>DRB1*04-DQB1*03<\/jats:italic> (<jats:italic>P<\/jats:italic> = 0.00014)<jats:italic>, DRB1*08-DQB1*03<\/jats:italic> (<jats:italic>P<\/jats:italic> = 0.027)<jats:italic>, DRB1*13-DQB1*02<\/jats:italic> (<jats:italic>P<\/jats:italic> = 0.004), and <jats:italic>DRB1*13-DQB1*03<\/jats:italic> (<jats:italic>P<\/jats:italic> = 3.79x10<jats:sup>-8<\/jats:sup>) were significantly associated with RA risk, while 3 protective haplotypes<jats:italic>, DRB1*03-DQB1*02<\/jats:italic> (<jats:italic>P<jats:sub>c<\/jats:sub><\/jats:italic> = 0.008), <jats:italic>DRB1*07-DQB1*02<\/jats:italic> (<jats:italic>P<jats:sub>c<\/jats:sub><\/jats:italic> = 0.004)<jats:italic>, and DRB1*13-DQB1*06<\/jats:italic> (<jats:italic>P<jats:sub>c<\/jats:sub><\/jats:italic> = 0.02) were identified. This is the first study determining the association between HLA class II alleles and haplotypes and RA risk in our population.<\/jats:p>","DOI":"10.3389\/fimmu.2023.1178546","type":"journal-article","created":{"date-parts":[[2023,6,24]],"date-time":"2023-06-24T05:21:51Z","timestamp":1687584111000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":16,"title":["Association of Human Leukocyte Antigen (HLA) class II (DRB1 and DQB1) alleles and haplotypes with Rheumatoid Arthritis in Sudanese patients"],"prefix":"10.3389","volume":"14","author":[{"given":"Adil Ahmed","family":"Ali","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Khalid Eltahir","family":"Khalid","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Somaya Elhaj","family":"Mohammed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed Salman","family":"Akhtar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Osman Khalafalla","family":"Saeed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2023,6,22]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1038\/gene.2008.77","article-title":"Rheumatoid arthritis: a view of the current genetic landscape","volume":"10","author":"Coenen","year":"2009","journal-title":"Genes Immun"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.pathol.4.110807.092254","article-title":"The immunopathogenesis of rheumatoid arthritis","volume":"4","author":"Imboden","year":"2009","journal-title":"Annu Rev Pathol"},{"key":"B3","article-title":"Influence of HLA-DR alleles on 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