Genetics of Allergy and Atopy
Allergic conditions including asthma, eczema, hay fever, and food allergy reflect dysregulated type 2 immune responses. Genetic variants in IgE regulation, cytokine pathways, and epithelial barrier genes influence atopic predisposition and allergy severity.
This page is for educational and informational purposes only. Not a diagnostic tool. Always consult a qualified healthcare provider.
What is Allergy and Atopy?
Type 2 immunity, mediated by Th2 cells, IgE antibodies, mast cells, and eosinophils, protects against parasites but drives allergic disease when misdirected. The atopic triad of asthma, eczema, and allergic rhinitis has a strong genetic component, with major contributions from FLG (filaggrin) variants affecting skin barrier integrity, IL4/IL13 signalling, and IgE regulation. In the context of Long COVID, new-onset allergic symptoms and mast cell activation have been reported, suggesting that prior atopic predisposition may interact with post-COVID immune dysregulation.
Biological pathways commonly discussed in relation to Allergy and Atopy
Research into Allergy, Atopy, and Type 2 Immune Responses has highlighted several biological pathways that may be relevant. Genetic variants within these pathways may influence individual susceptibility, symptom severity, or the trajectory of the condition.
Type2 Immunity
Th2 cells produce IL-4, IL-5, IL-13, and IL-33, driving IgE class switching and mast cell and eosinophil activation. Variants in IL4, IL13, GATA3, and IL33 influence Th2 immune polarisation.
Ige Regulation
IgE antibodies mediate allergic responses by sensitising mast cells and basophils. Variants in IL4RA, FCER1A, and total IgE regulation genes influence allergic sensitisation thresholds.
Epithelial Barrier
FLG (filaggrin) null variants are the strongest genetic risk factor for atopic dermatitis. They reduce skin barrier integrity, allowing allergen sensitisation. TSLP variants also influence epithelial alarm cytokine production.
Eosinophil Biology
Eosinophils drive allergic inflammation in airways and tissues. IL-5 (encoded by IL5) and its receptor (IL5RA) regulate eosinophil development and survival.
Key genes studied in relation to Allergy and Atopy
The following genes have been studied in relation to Allergy, Atopy, and Type 2 Immune Responses. These genes span the biological pathways most commonly discussed in this area of research.
14 genes total studied in relation to Allergy and Atopy across the ChronicDNA dataset.
Genetic variants commonly discussed
The following genetic variants (SNPs) are found in genes that have been studied in relation to Allergy and Atopy. Each variant represents a position in the genome where individuals may carry different alleles.
40 variants total across genes studied in relation to Allergy and Atopy.
How personal DNA data may provide educational insights
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 relate to areas such as Allergy and Atopy.
This is not a diagnostic service. Genetic variants do not determine whether you have Allergy and Atopy, nor do they predict your clinical outcomes. 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. All results should be discussed with a qualified healthcare provider.
Related conditions and pathways
Allergy and Atopy shares biological pathways and genetic associations with the following related conditions and areas of research.
Frequently asked questions
What is the genetic basis of allergy?
Allergy has a strong genetic component involving FLG (skin barrier), IL4/IL13 signalling, IgE regulation genes (IL4RA, FCER1A), and Th2 cytokine pathway genes. No single gene determines allergy — multiple variants interact with environmental allergen exposure.
How does allergy relate to Long COVID or MCAS?
Pre-existing atopic conditions and mast cell hyperreactivity may interact with post-COVID immune dysregulation to worsen allergic symptoms or precipitate MCAS. New-onset allergic reactions following COVID-19 have been reported in some patients.
What is the filaggrin gene and why is it important?
FLG encodes filaggrin, a protein essential for skin barrier integrity. Null variants in FLG are found in approximately 10% of Northern European individuals and are the strongest single genetic risk factor for atopic dermatitis, also predisposing to asthma and food allergy.
Which allergy genes are included in consumer DNA data?
Consumer DNA datasets may include FLG variants, IL4RA variants, and FCER1A variants. ChronicDNA analyses these in the educational context of immune pathway biology.
Explore DNA insights
If you already have DNA data from 23andMe, AncestryDNA, or MyHeritage, upload your raw file to ChronicDNA and receive a personalised educational report covering genes studied in relation to Allergy and Atopy and connected biological pathways.
Get Your Personalised DNA ReportInformational and educational only · Not a diagnostic tool · GDPR compliant
14 genes · 40 variants analysed in relation to Allergy and Atopy