High-Resolution HLA Allele and Haplotype Frequencies in a Southern Brazilian Population

The HLA system has been extensively studied due to its crucial role in the immune system, as well as its application in population, anthropological and epidemiological research. This study analysed 11 loci of HLA allele and haplotype frequency (HLA-A, -B, -C, -DRB1, -DQA1, -DQB1, -DPA1, -DPB1 and -DRB3/4/5) using high-resolution next-generation sequencing technology. A total of 5287 volunteer bone marrow donors from the Northwestern region of the state of Paraná, in Southern Brazil, were rated. Most of the analysed loci were in Hardy-Weinberg equilibrium, except for HLA-DPA1 and -DPB1. The most frequent alleles were HLA-A*02:01:01, HLA-B*51:01:01 and HLA-C*04:01:01 for Class I and DRB1*07:01:01, DRB3*02:02P, DRB4*01:01P, DRB5*01:01P, DQA1*01:02:01, DQB1*05:01:01, DPA1*01:03:01 and DPB1*04:01:01 for Class II. The most prevalent haplotype for ABCDRB1 alleles was HLA-A*01:01:01~B*08:01:01~C*07:01:01~DRB1*03:01:01, which is typical of European descents. These results reflect a predominantly European genetic contribution, with additional African and Native American influences. These data extend understanding of genetic diversity about the Brazilian HLA system and provide information to characterise this population's HLA profile.