LAG3 Gene

What is the LAG3 gene?

LAG3 encodes lymphocyte activating gene 3, a protein involved in T cell exhaustion / co-inhibitory checkpoint. It belongs to the Immune Signaling category and is part of the Immune System & Inflammation biological cluster. LAG3 encodes lymphocyte activation gene 3, a co-inhibitory receptor on exhausted T cells that dampens T cell effector function.

Biological role and pathway

LAG3 is involved in the T cell exhaustion / co-inhibitory checkpoint pathway, which plays a central role in regulating physiological processes relevant to immune defence, cellular energy, and systemic homeostasis. Genes within the Immune System & Inflammation 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.

Known genetic variants

The following variants (SNPs) in the LAG3 gene have been studied in relation to immune signaling and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

• rs870849— LAG3 variant

Conditions studied in relation to LAG3

Research into LAG3 variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that LAG3 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 LAG3 and related genes in the immune system & inflammation 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 Immune System & Inflammation pathway

LAG3 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