DEFB1 Gene

What is the DEFB1 gene?

DEFB1 encodes defensin beta 1, a protein involved in antimicrobial defense. It belongs to the Innate Immunity category and is part of the Gut-Brain Axis biological cluster. DEFB1 is a constitutively expressed antimicrobial peptide in epithelial cells of the gut, respiratory tract, and urogenital system. It has direct antimicrobial activity and functions as a chemokine for dendritic cells and T cells.

Biological role and pathway

DEFB1 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.

Known genetic variants

The following variants (SNPs) in the DEFB1 gene have been studied in relation to innate immunity and chronic illness. Each variant represents a single nucleotide position where individuals may carry different alleles.

• rs11362— DEFB1 variant
• rs2741160— DEFB1 variant
• rs1800972— DEFB1 variant

Conditions studied in relation to DEFB1

Research into DEFB1 variants has explored associations with the following conditions. These are areas of scientific investigation and do not imply that DEFB1 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 DEFB1 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

DEFB1 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