HLA alleles and haplotype frequencies in Iranian population.

BACKGROUND: HLA genotyping is a prerequisite for selection of suitable donors in the process of bone marrow transplantation. METHODS: In the current study, the frequencies of HLA-A, -B, -C and -DRB1 alleles and A-B-C-DRB1 haplotypes were assessed in 855 healthy Iranian persons using a low-resolution sequence specific primer (SSP) kit. RESULTS: Frequencies were compared between 11 subpopulations including Armani, Balouch, Bandari, Turk, Turkaman, Arab, Fars, Kurd, Gilaki, Lor and Mazani. In total, 17 HLA-A alleles were detected, one of which (HLA-A*74) was present only among Lors. HLA-A*23 and -A*26 were the most frequent HLA-A alleles among Armanis. HLA-A*23 was also common among Turkamans. HLA-A*11 and -A*26 were most frequent among the Balouch subpopulation. The former allele was also frequent among Bandaris. HLA-A*02 was identified as the most common HLA-A allele among Turk, Arab and Fars subpopulations. HLA-A*30 were strongly enriched among Gilakis. A total of 31 HLA-B alleles were detected across the target population. While all alleles were present among Fars subgroup, Armanis and Turkamans had the lowest degree of diversity among the alleles examined. Moreover, HLA-B*35 and B*49 alleles were strongly enriched among Armanis and Turkamans, respectively. A total of 13 HLA-C alleles were identified across the population, all of which were present in the Fars subpopulation. HLA-C*03 and C*04 were the only HLA-C alleles identified among the Bandari subpopulation. HLA-DRB1*08 was not detected in any subpopulation other than Fars. HLA-DRB1*16 was significantly enriched among Bandaris. These data have practical significance in anthropological studies, disease association investigations and bone marrow transplantation.

Identification of HLA-A/B/DRB1 alleles in Iranian patients with Fanconi anemia.

Fanconi anemia includes a number of clinically and genetically diverse disorders all of them being associated with genomic instability. Some previous studies reported higher frequencies of certain HLA alleles in patients with Fanconi anemia. In the current study, we genotyped HLA-A/B/DRB1 alleles in 40 Iranian patients with Fanconi anemia. We also genotyped these alleles in the same number of Iranian sex-matched healthy individuals. The frequency of DRB1*11 was significantly higher in patients compared with controls (OR (95% CI) = 2.143 [1.05, 4.46], P value = 0.036). On the other hand, the frequencies of DRB1*13 and B*13 were lower in patients compared with controls (OR (95% CI) = 0.134 [0.02, 0.55], P value = 0.003 and OR (95% CI) = 0.13 [0.01, 0.89], P value = 0.035, respectively). Assessment of genetic divergence using Fstat test showed complete divergence in HLA-A, -B, -DRB1 alleles and haplotypes between patients and controls. The current study provides evidences for different distribution of HLA alleles between patients with Fanconi anemia and healthy subjects.