Screening of HLA-A, HLA-B, and HLA-DRB1 Allele Frequencies in the Iraqi Population: Implications for Precision Therapy
Keywords:
Human Leukocyte Antigens, precision medicine, Iraqi populationAbstract
Background: Understanding the diversity of human leukocyte antigens (HLA) is crucial for personalized therapy, enabling tailored treatments with minimal adverse effects. This study aims to identify the prevalence of HLA alleles in the Iraqi population, contributing to precision medicine and enhancing therapeutic strategies through insights into genetic factors. Methods: A total of 300 healthy adults (192 males, mean age 36.98 ± 10.18 years; 108 females, mean age 34.53 ± 9.9 years) from Baghdad participated in this study. Volunteers had no chronic diseases, and peripheral blood samples were collected for genotyping. DNA was extracted using the ReliaPrepTM Blood gDNA Miniprep Kit (Promega-USA) and stored at -20°C. HLA class I (HLA-A, HLA-B) and class II (HLA-DRB1) alleles were genotyped using PCR-SSO. Results: The study identified significant frequencies, with the highest observed for HLA class I alleles: A*02:01 (25.33%), A*03:01 (12.83%), A*01:01 (9.5); B*35:01 (10.16%), B*50:01 (8.15%) and B*50:02 (6%), while the least common alleles identified in the study were A*02:03, A*02:05, A*11:02, A*11:12, A*26:05, A*29:02, A*30:02, A*31:03, A*33:03 and A*36:01 each with a frequency of (0.16%); B*08:27 B*13:03, B*27:01, B*42:02, B*51:04, B*51:151 and B*51:51 were (0.16%). For HLA class II alleles, The three most prevalent HLA class II alleles are DRB1*03:01 (17.16%), DRB1*07:01 (16.5%), and DRB1*13:01 (12.33%). Conversely, the least common alleles, comprising DRB1*01:03, DRB1*03:03 DRB1*04:06, DRB1*04:145, DRB1*09:01, DRB1*09:02, DRB1*11:06, DRB1*12:01, DRB1*13:07, DRB1*13:256, DRB1*14:02, DRB1*14:99 and DRB1*15:02, exhibit a prevalence of 0.16%. This study highlights the diversity of HLA genes in the Iraqi population, which is crucial for advancing precision medicine by enabling tailored treatments and optimizing therapeutic strategies. Conclusion: Considering several genetic markers, HLA class I and II allelic frequencies, as well as linkage disequilibrium patterns, are crucial in determining genetic relationships. Therefore, the variation in HLA alleles and haplotypes is extensively used to study the origins and migrations of human populations.
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