IL4R rs1805015: Understanding the I50V Genetic Variant
The rs1805015 variant is a well-characterized genetic change located in the IL4R gene. It is frequently studied for its potential role in modulating immune system signaling pathways related to allergic responses and asthma.
What each genotype means
Baseline IL-4 receptor activity
This genotype represents the common form of the IL4R gene. Research into this variant focuses on its potential role in immune signaling pathways, though clinical implications for individuals remain limited and require further study.
This is a common genotype found across global populations.
Intermediate IL-4 receptor variant
Carrying one copy of the variant allele may influence IL-4 receptor signaling, which is involved in allergic and immune responses. Current evidence regarding the health impact of this specific genotype is limited, and it should not be used to predict individual health outcomes.
This heterozygous genotype is frequently observed in diverse populations worldwide.
Enhanced IL-4 receptor signaling
This genotype is associated with the I50V missense variant, which has been studied for its potential to enhance downstream allergic and Th2 signaling pathways. Some research has explored its association with survival outcomes in specific clinical contexts like high-grade glioma, but these findings are limited and not diagnostic. Please discuss any health concerns or clinical questions with your healthcare provider.
This genotype is present in a significant portion of the population, with the minor allele frequency ranging between 0.35 and 0.50 globally.
What is rs1805015?
The rs1805015 variant is a single-nucleotide polymorphism (SNP) located on chromosome 16. In the context of the IL4R gene, this specific variant results in a missense mutation, meaning it causes a change in the amino acid sequence of the resulting protein. Specifically, it is often referred to as the I50V variant, where an isoleucine (I) is replaced by a valine (V) at position 50 of the IL-4 receptor alpha chain. Because this change occurs within the coding region of the gene, it has the potential to alter the structure or function of the receptor itself. Researchers track this variant to understand how subtle changes in protein structure might influence biological processes, particularly those involving the immune system's response to external triggers.
The Role of the IL4R Gene
The IL4R gene provides instructions for creating the alpha subunit of the interleukin-4 receptor. This receptor is a critical component of the immune system, acting as a docking site for interleukin-4 (IL-4) and interleukin-13 (IL-13), which are signaling molecules known as cytokines. When these cytokines bind to the receptor, they trigger a cascade of signals inside the cell that regulate immune responses, including the activation and differentiation of various white blood cells. This pathway is particularly important in the development of allergic inflammation and the production of immunoglobulin E (IgE), an antibody involved in allergic reactions. By influencing how cells respond to these cytokines, the IL4R gene plays a central role in maintaining the balance of the immune system's inflammatory responses.
Research and Associations
Scientific research has investigated the association between the rs1805015 variant and various immune-related conditions, most notably asthma and atopy. Some studies suggest that this variant may act as a gain-of-function mutation, potentially enhancing downstream signaling pathways that promote airway inflammation and mast cell activity. While these findings have been observed in clinical and laboratory settings, the evidence remains limited and sometimes mixed across different populations. It is important to note that asthma is a complex, polygenic condition influenced by many genetic and environmental factors. Therefore, the presence of this variant does not guarantee the development of any specific health condition. Current research continues to explore how this variant interacts with other genetic markers and environmental triggers to influence individual immune profiles.
Population Frequency
The rs1805015 variant is considered a common genetic variation. According to data from the Genome Aggregation Database (gnomAD), the minor allele frequency typically ranges between 0.35 and 0.50 across various global populations. This high frequency indicates that the variant is widely distributed and present in a significant portion of the human population. Because it is so common, it is often studied in the context of population-wide genetic diversity rather than as a rare, disease-causing mutation. Understanding its prevalence helps researchers contextualize its potential impact on immune function across different ancestral backgrounds.
Interpreting Your Information
Genetic information like the rs1805015 variant provides a snapshot of your biological blueprint, but it is not a diagnostic tool. Because the associations between this variant and health outcomes are complex and influenced by many other factors, you cannot use this information to predict or diagnose medical conditions. If you have concerns about your immune health, allergies, or asthma, it is essential to consult with a qualified healthcare professional. They can evaluate your symptoms, medical history, and other relevant factors to provide appropriate guidance. Never make changes to your medications or treatment plans based on genetic data without first discussing them with your doctor or pharmacist, as they are the only ones qualified to interpret your results in the context of your overall health.
How common is this variant?
The rs1805015 variant is common, with a minor allele frequency of approximately 0.35–0.50 across global populations as reported in gnomAD.
Frequently asked questions
Does having the rs1805015 variant mean I have asthma?
No, having this variant does not mean you have or will develop asthma. Asthma is a complex condition influenced by many genetic and environmental factors, and this variant is only one of many potential contributors.
Can I use this genetic information to change my allergy medication?
You should never change your medication based on genetic information alone. Always discuss your treatment plan and any potential adjustments with your doctor or pharmacist.
Is rs1805015 considered a rare mutation?
No, rs1805015 is a common genetic variant found in a significant percentage of the global population. It is not considered a rare, disease-causing mutation.
Where can I find more information about my specific genotype?
If you have received genetic testing results, you should consult with a genetic counselor or your primary care physician. They can help you understand your results in the context of your personal and family health history.
Sources & further reading
Educational information only, last refreshed 10/10/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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A polymorphism modulating IL-4 and IL-13 signaling thresholds on mucosal surfaces, conferring altered predisposition to aeroallergen reactivity.
Variant in the IL4R locus associated with atopic dermatitis and allergic rhinitis susceptibility.
Missense variant (p.Gln551Arg) in interleukin 4 receptor subunit alpha strongly linked to atopic asthma and IgE regulation.
A functional variant within the IL4R promoter/intron region modulating receptor density and susceptibility to atopic eczema and allergic rhinitis.
A coding missense variant (Q576R) in the IL-4 receptor alpha chain that potentiates downstream STAT6 signaling, increasing predisposition to atopic asthma and severe allergic sensitization.
A missense variant in the interleukin 4 receptor alpha chain that impacts signaling sensitivity and is associated with allergic bronchopulmonary disorders and atopic dermatitis.