HLAA0201

HLAA0201 is a shorthand designation used in immunogenetics to refer to the HLA-A02:01 allele, a member of the HLA class I gene family. It is part of the HLA-A2 serotype and is one of the most common HLA class I alleles worldwide, with varying frequencies among different populations. The designation HLAA0201 is often encountered in databases and older literature, while the precise nomenclature uses HLA-A02:01.

In the immune system, HLA-A02:01 encodes a cell-surface glycoprotein that presents endogenously derived peptide fragments to CD8+ T cells. The peptide binding repertoire of A02:01 influences cytotoxic T cell responses to infections and tumors and contributes to immune recognition and surveillance. Variation at this locus can affect peptide affinity and presentation, which has implications for vaccine design, infection outcomes, and transplant biology.

In clinical and research settings, HLAA0201 is used for donor–recipient compatibility assessment in hematopoietic stem cell and solid organ transplantation. Typing methods include sequence-based typing, sequence-specific oligonucleotide probes, and next-generation sequencing, which can distinguish HLA-A02:01 from closely related alleles. Population frequency data for HLAA0201 are maintained in allele registries and vary by ethnicity and region. The nomenclature HLAA0201 is largely superseded in formal contexts by HLA-A02:01, with additional allelic and haplotype details as needed. See also HLA-A02:01.