ADAM33 rs3918396: What Your Genotype Means
The rs3918396 variant is a single nucleotide polymorphism located within the ADAM33 gene. It has been studied for its potential statistical association with asthma susceptibility and chronic obstructive pulmonary disease (COPD) risk in certain populations.
What each genotype means
Typical asthma risk profile
This genotype represents the more common version of this variant in many populations. Research suggests this version is not associated with the increased risk of asthma observed with the alternative allele. This result does not rule out the possibility of developing asthma, as the condition is influenced by many genetic and environmental factors.
This is the most frequently observed genotype in many global populations.
Intermediate asthma risk profile
Carrying one copy of the A allele may be associated with a moderate increase in asthma susceptibility compared to those without it. Because asthma is a complex, polygenic condition, this genetic finding is only one small piece of the puzzle. Please discuss your respiratory health and any symptoms with your healthcare provider.
This genotype is found at varying frequencies depending on ancestral background, appearing in a significant portion of the population.
Increased asthma risk profile
Studies have identified this specific genotype as being associated with a higher statistical risk for asthma in certain populations. This variant is located in the ADAM33 gene, which is involved in airway remodeling and inflammation. This finding is a statistical association and not a diagnosis; please consult with a clinician to discuss your personal health history and any respiratory concerns.
This genotype is less common than the others and its prevalence varies significantly across different ethnic and geographic groups.
Understanding the rs3918396 Variant
The rs3918396 variant is a specific change in the DNA sequence of the ADAM33 gene. In genetics, a single nucleotide polymorphism (SNP) like rs3918396 represents a variation at a single position in the genome. This variant is located within the ADAM33 gene, which provides instructions for making a protein known as ADAM metallopeptidase domain 33. Researchers study these variants to understand how small differences in our genetic code might influence biological processes. It is important to note that the presence of a specific variant does not guarantee the development of any condition; rather, it is one of many factors that scientists investigate when looking at complex traits like respiratory health. Genetic associations are typically identified through large-scale studies that compare the frequency of specific alleles in groups of people with and without a particular trait.
The Role of the ADAM33 Gene
The ADAM33 gene encodes a protein that belongs to the ADAM (A Disintegrin And Metalloprotease) family. This protein is primarily expressed in mesenchymal cells, such as fibroblasts and smooth muscle cells, which are found in the airways of the lungs. ADAM33 is thought to play a role in airway remodeling, a process where the structure of the airways changes over time, potentially affecting lung function. Because of its expression in lung tissue, researchers have long hypothesized that variations in this gene could influence how the lungs respond to environmental triggers. While the exact biological mechanism by which specific SNPs like rs3918396 might alter protein function or expression is still a subject of ongoing research, the gene remains a significant candidate in studies exploring the genetic basis of bronchial hyperresponsiveness and other pulmonary conditions.
Research and Evidence Strength
The evidence linking ADAM33 variants to asthma and COPD is considered moderate and has been a subject of extensive scientific debate. While early studies identified ADAM33 as a susceptibility gene for asthma, subsequent replication studies have yielded mixed results across different ethnic and geographic populations. Some research has suggested that rs3918396 may be associated with an increased risk of COPD, particularly in individuals who smoke. However, other studies have found no significant association between individual ADAM33 SNPs and disease predisposition, leading some researchers to suggest that the risk may be tied to specific haplotypes—groups of variants inherited together—rather than a single SNP. Because of these conflicting findings, the scientific community views the role of rs3918396 as a complex association that likely depends on gene-environment interactions and the specific genetic background of the population being studied.
Interpreting Your Genetic Information
If you have information about your rs3918396 genotype, it is important to understand that this data is for educational purposes only. Genetic variants are not diagnostic tools; they cannot predict whether you will develop asthma or COPD. Respiratory conditions are complex, influenced by a combination of genetics, lifestyle factors, and environmental exposures. You cannot change your genotype, but you can manage your health by working with a healthcare professional to monitor your lung function and minimize exposure to known triggers like tobacco smoke or allergens. If you are concerned about your respiratory health or have questions about how your genetic profile might relate to your medical history, please discuss these findings with your doctor or a genetic counselor. They can provide context based on your personal health history and help you make informed decisions about your care.
How common is this variant?
Specific global frequency data for rs3918396 is not consistently recorded in major public databases, and its prevalence varies significantly across different ancestral populations.
Frequently asked questions
Does having the rs3918396 variant mean I will get asthma?
No. Having a specific variant does not mean you will develop asthma. Asthma is a complex condition influenced by many genetic and environmental factors, and this variant is only one small piece of a much larger puzzle.
Is rs3918396 a diagnostic test for lung disease?
No, this variant is not used for medical diagnosis. Genetic associations are statistical observations in populations and cannot be used to predict individual health outcomes or diagnose medical conditions.
What should I do if I have the 'higher-attention' genotype?
You should continue to focus on general respiratory health, such as avoiding smoking and minimizing exposure to air pollutants. If you have concerns about your lung health, consult your physician for a clinical evaluation.
Why do some studies say ADAM33 is linked to asthma while others do not?
Genetic associations can vary between populations due to differences in genetic background and environmental exposures. This is common in complex traits, where the effect of a single variant may be small or dependent on other factors.
Sources & further reading
Educational information only, last refreshed 9/23/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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Intronic susceptibility variant in the metalloproteinase ADAM33 gene associated with allergic hyperresponsiveness and atopic airway remodeling.
Noncoding functional polymorphism in the asthma and allergy risk gene ADAM33 linked to altered bronchial reactivity and atopic susceptibility.
This variant is part of a haplotype associated with increased risk of asthma in patient populations.
This variant is part of a haplotype in the ADAM33 gene that shows significant association with asthma susceptibility and IgE levels in specific patient populations.