AUTHOR=Ali Adil Ahmed , Khalid Khalid Eltahir , Mohammed Somaya Elhaj , Akhtar Mohammed Salman , Saeed Osman Khalafalla 

TITLE=Association of Human Leukocyte Antigen (HLA) class II (DRB1 and DQB1) alleles and haplotypes with Rheumatoid Arthritis in Sudanese patients

JOURNAL=Frontiers in Immunology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2023.1178546

DOI=10.3389/fimmu.2023.1178546

ISSN=1664-3224

ABSTRACT=<p>The aim of this study was to determine the Human Leukocyte Antigen (HLA) class II (<italic>DRB1</italic> and <italic>DQB1</italic>) alleles and haplotype frequency in Rheumatoid Arthritis <bold>(</bold>RA) in the Sudanese population. The frequency of <italic>HLA-DRB1</italic> and -<italic>DQB1</italic> alleles and <italic>DRB1-DQB1</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, <italic>HLA-DRB1*04 and *10</italic> alleles were high in frequency (9.6% vs 14.2%, <italic>P</italic> = 0.038 and <italic>P</italic> = 0.042, respectively), and dependently on anti-citrullinated protein antibodies (ACPAs) seropositivity (<italic>P</italic> = 0.044 and <italic>P</italic> = 0.027, respectively). In contrast, the frequency of the <italic>HLA-DRB1*07</italic> allele was significantly low in patients than in controls (11.7% vs 5.0%, <italic>P</italic> = 0.010). Moreover, the <italic>HLA-DQB1*03</italic> allele was strongly associated with RA risk (42.2%, <italic>P</italic> = 2.2x10<sup>-8</sup>), whereas, <italic>HLA-DQB1*02</italic> and <italic>*06</italic> showed protective effects against RA (23.1% and 42.2%, <italic>P</italic> = 0.024 and <italic>P</italic> = 2.2x10<sup>-6</sup>, respectively). Five different HLA haplotypes, <italic>DRB1*03-DQB1*03</italic> (<italic>P</italic> = 0.00003), <italic>DRB1*04-DQB1*03</italic> (<italic>P</italic> = 0.00014)<italic>, DRB1*08-DQB1*03</italic> (<italic>P</italic> = 0.027)<italic>, DRB1*13-DQB1*02</italic> (<italic>P</italic> = 0.004), and <italic>DRB1*13-DQB1*03</italic> (<italic>P</italic> = 3.79x10<sup>-8</sup>) were significantly associated with RA risk, while 3 protective haplotypes<italic>, DRB1*03-DQB1*02</italic> (<italic>P<sub>c</sub></italic> = 0.008), <italic>DRB1*07-DQB1*02</italic> (<italic>P<sub>c</sub></italic> = 0.004)<italic>, and DRB1*13-DQB1*06</italic> (<italic>P<sub>c</sub></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.</p>