HLA-DRB1 and thalassemia: A total of 22 risk genotypes of thalassemia consisted of 13 class I (5 for A, 6 for B, and 2 for C) and 9 class II genotypes (5 and 4 for DQB1 and DRB1, respectively), with B*46:01-B*58:01 (OR: 2.32; 95% CI: 1.48–3.65, Pc = 0.01), C*01:02-C*03:04 (OR: 2.08; 95% CI: 1.51–2.87, Pc <0.01), DQB1*03:01-DQB1*05:02 (OR: 2.35; 95% CI: 1.70–3.24, Pc <0.01), and DRB1*14:54-DRB1*15:01 (OR: 3.87; 95% CI: 2.38–6.32, Pc <0.01) occurred most frequently (Table 3).