FASN Gene

Fatty Acid Synthase (FASN) is a gene involved in de novo fatty acid synthesis that has been studied in relation to immune function, metabolism, and chronic illness. Variants in FASN 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 FASN gene?

FASN encodes fatty acid synthase, a protein involved in de novo fatty acid synthesis. It belongs to the Lipid Metabolism category and is part of the Lipid Metabolism biological cluster. FASN encodes fatty acid synthase, the multifunctional enzyme catalyzing de novo synthesis of palmitate from acetyl-CoA.

Biological role and pathway

FASN is involved in the de novo fatty acid synthesis pathway, which plays a central role in regulating physiological processes relevant to immune defence, cellular energy, and systemic homeostasis. Genes within the Lipid Metabolism 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.

FASN and Long COVID / ME-CFS research

FASN-mediated lipogenesis is reprogrammed during viral infection; altered fatty acid synthesis may contribute to immune cell dysfunction 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 FASN gene have been studied in relation to lipid metabolism and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

Conditions studied in relation to FASN

Research into FASN variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that FASN 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 FASN and related genes in the lipid metabolism 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 Lipid Metabolism pathway

FASN 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 FASN gene and what does it do?

FASN (Fatty Acid Synthase) is involved in de novo fatty acid synthesis. FASN encodes fatty acid synthase, the multifunctional enzyme catalyzing de novo synthesis of palmitate from acetyl-CoA.

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

FASN-mediated lipogenesis is reprogrammed during viral infection; altered fatty acid synthesis may contribute to immune cell dysfunction in Long COVID.

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

  • [1]PMID: 34316049
  • [2]Nature Genetics
  • [3]Journal of Clinical Investigation