HLA-A Gene

Major Histocompatibility Complex Class I A (HLA-A) is a gene involved in MHC class I antigen presentation that has been studied in relation to immune function, metabolism, and chronic illness. Variants in HLA-A may influence how the body responds to infection, inflammation, and long-term recovery.

This page is for educational and informational purposes only. Not a diagnostic tool. Always consult a qualified healthcare provider.

What is the HLA-A gene?

HLA-A encodes major histocompatibility complex class i a, a protein involved in MHC class I antigen presentation. It belongs to the Immune Presentation category and is part of the HLA & Immune Presentation biological cluster. HLA-A encodes an MHC class I molecule that presents intracellular peptides to cytotoxic CD8+ T lymphocytes.

Biological role and pathway

HLA-A is involved in the MHC class I antigen presentation pathway, which plays a central role in regulating physiological processes relevant to immune defence, cellular energy, and systemic homeostasis. Genes within the HLA & Immune Presentation cluster work together to maintain balanced function across interconnected biological systems.

Variants in genes within this pathway may influence an individual's predisposition to altered function in these systems — particularly under conditions of physiological stress such as viral infection or prolonged illness.

HLA-A and Long COVID / ME-CFS research

HLA-A alleles determine the repertoire of viral peptides presented to cytotoxic T cells and may influence Long COVID immune memory.

This information is based on published research and does not constitute medical advice. See references below.

Known genetic variants

The following variants (SNPs) in the HLA-A gene have been studied in relation to immune presentation and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

Conditions studied in relation to HLA-A

Research into HLA-A variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that HLA-A causes or treats any condition.

Genetic insights from DNA data

Consumer DNA files from 23andMe, AncestryDNA, and MyHeritage contain raw SNP data. When you upload your file to ChronicDNA, the analysis engine checks your genotype against a curated panel of 80+ genes selected for their relevance to Long COVID, ME/CFS, and connected biological pathways - some of which may include HLA-A and related genes in the hla & immune presentation pathway.

The report is educational - it explains which variants you carry, what the research says about them, and how they fit into the biological pathways most relevant to chronic illness. Results are presented in plain English with appropriate scientific context, no medical jargon, no scare tactics. All results should be discussed with a qualified healthcare provider.

Related genes in the HLA & Immune Presentation pathway

HLA-A does not act in isolation. The following genes are functionally related and may be analysed together for a more complete picture of your genetic predispositions.

Frequently asked questions

What is the HLA-A gene and what does it do?

HLA-A (Major Histocompatibility Complex Class I A) is involved in MHC class I antigen presentation. HLA-A encodes an MHC class I molecule that presents intracellular peptides to cytotoxic CD8+ T lymphocytes.

How may HLA-A gene variants relate to Long COVID or ME/CFS?

HLA-A alleles determine the repertoire of viral peptides presented to cytotoxic T cells and may influence Long COVID immune memory.

Can a DNA test reveal information about my HLA-A gene?

Consumer DNA data from 23andMe, AncestryDNA, and MyHeritage includes SNP variants for many genes. ChronicDNA analyses your raw DNA file and reports on variants that have been studied in relation to chronic illness, immune function, and metabolism. This is not a diagnostic service — results are informational and educational only.

Explore your HLA-A genetic insights

Upload your DNA data from 23andMe, AncestryDNA, or MyHeritage and receive a personalised report covering >80 genes relevant to Long COVID and ME/CFS.

Get Your Personalised DNA Report

Informational and educational only · Not a diagnostic tool · GDPR compliant

References

The following publications were used in compiling the research context for HLA-A. This is not an exhaustive literature review.

  • [1]PMID: 33888513
  • [2]Nature Genetics
  • [3]Journal of Clinical Investigation