Allele and haplotype frequencies in high-resolution typing of human leukocyte antigen -A,-B, -C, -DRB1, and -DQB1 in 263,542 Thai voluntary stem cell donors.

The human leukocyte antigen (HLA) allele and haplotype frequencies were calculated from 263,542 voluntary donors with medium- to high-resolution typing. This is the first study of a large sample with high-resolution HLA typing in the Thai population. The total numbers of two-field single alleles for HLA-A, -B, -C, -DRB1, and -DQB1 were 139, 198, 115, 80, and 24, respectively. The proportion of each HLA allele in Thais ranged from 1.54% to 3.45% of the total two-field HLA alleles in the IPD-IMGT/HLA database. The frequencies of alleles following common, intermediate, and well-documented (CIWD) groups for HLA-A, -B, -C,-DRB1, and -DQB1 were 69, 123, 55, 69, and 18, respectively. The CIWD percentages were 49.64%, 62.12%, 47.83%, 86.25%, and 75.0%, respectively. The alleles with a frequency greater than 5% were A*02:03, A*02:07, A*11:01, A*24:02, A*33:03, B*13:01, B*15:02, B*40:01, B*46:01, B*58:01, C*01:02, C*03:02, C*03:04, C*07:01, C*07:02, C*08:01, DRB1*03:01, DRB1*04:05, DRB1*07:01, DRB1*09:01, DRB1*12:02, DRB1*15:01, DRB1*15:02, DRB1*16:02, DQB1*02:01, DQB1*03:01, DQB1*03:02, DQB1*03:03, DQB1*05:01, DQB1*05:02, and DQB1*06:01. The haplotypes with a frequency greater than 2% were A*02:07 ∼ C*01:02 ∼ B*46:01 ∼ DRB1*09:01 ∼ DQB1*03:03, A*11:01 ∼ C*08:01 ∼ B*15:02 ∼ DRB1*12:02 ∼ DQB1*03:01, A*33:03 ∼ C*03:02 ∼ B*58:01 ∼ DRB1*03:01 ∼ DQB1*02:01,and A*33:03 ∼ C*07:01 ∼ B*44:03 ∼ DRB1*07:01 ∼ DQB1*02:01. These findings enable the registry to predict the opportunity to find well-matched organ and stem cell donors for patients with rare HLA typing.