REG3A Gene

Regenerating Family Member 3 Alpha (REG3A) is a gene involved in antimicrobial defense that has been studied in relation to immune function, metabolism, and chronic illness. Variants in REG3A 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 REG3A gene?

REG3A encodes regenerating family member 3 alpha, a protein involved in antimicrobial defense. It belongs to the Gut Barrier category and is part of the Gut-Brain Axis biological cluster. REG3A (HIP/PAP) is a secreted C-type lectin with antimicrobial activity against gram-positive bacteria, expressed in intestinal epithelium and liver. It is induced by gut bacteria and maintains spatial separation between microbiota and the epithelial surface.

Biological role and pathway

REG3A is involved in the antimicrobial defense pathway, which plays a central role in regulating physiological processes relevant to immune defence, cellular energy, and systemic homeostasis. Genes within the Gut-Brain Axis 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.

REG3A and Long COVID / ME-CFS research

REG3A is a marker of gut barrier function and acute-phase response elevated in COVID-19. Variants affecting REG3A-mediated antimicrobial defense may alter gut microbiome composition, influencing the immune dysregulation in Long COVID.

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 REG3A gene have been studied in relation to gut barrier and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

Conditions studied in relation to REG3A

Research into REG3A variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that REG3A 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 REG3A and related genes in the gut-brain axis 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 Gut-Brain Axis pathway

REG3A 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 REG3A gene and what does it do?

REG3A (Regenerating Family Member 3 Alpha) is involved in antimicrobial defense. REG3A (HIP/PAP) is a secreted C-type lectin with antimicrobial activity against gram-positive bacteria, expressed in intestinal epithelium and liver. It is induced by gut bacteria and maintains spatial separation between microbiota and the epithelial surface.

How may REG3A gene variants relate to Long COVID or ME/CFS?

REG3A is a marker of gut barrier function and acute-phase response elevated in COVID-19. Variants affecting REG3A-mediated antimicrobial defense may alter gut microbiome composition, influencing the immune dysregulation in Long COVID.

Can a DNA test reveal information about my REG3A 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 REG3A 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 REG3A. This is not an exhaustive literature review.

  • [1]PMID: 31907413
  • [2]Nature Immunology
  • [3]Gut Microbes