IL2 rs13151961: What Your Genotype Means
The rs13151961 variant is a single nucleotide polymorphism located within the IL2/IL21 gene region on chromosome 4. Research has identified a statistically significant association between this variant and an altered risk for developing ulcerative colitis.
What each genotype means
Typical risk profile
This genotype is the most common in many populations. Research indicates that this variant in the IL2/IL21 region is associated with susceptibility to ulcerative colitis, and this specific genotype represents the baseline risk level observed in these studies.
This is the most frequent genotype observed in European populations.
Increased risk association
Individuals with this genotype carry one copy of the minor allele. Studies have identified this variant as a susceptibility locus for ulcerative colitis, and carrying this allele is statistically associated with an increased risk of developing the condition compared to those without it.
This genotype is found in a minority of individuals of European ancestry.
Elevated risk association
This genotype includes two copies of the minor allele associated with the IL2/IL21 locus. Research has linked this variant to a higher statistical association with ulcerative colitis susceptibility. Please note that genetic associations are complex and do not constitute a medical diagnosis.
This is the least common genotype, occurring in a small percentage of the European population.
Understanding the rs13151961 Variant
The rs13151961 variant is a specific change in the DNA sequence located in a region of chromosome 4 that houses the IL2 and IL21 genes. In genetics, a single nucleotide polymorphism, or SNP, represents a variation at a single position in the DNA sequence among individuals. This particular SNP has been the subject of multiple genetic association studies, which look for correlations between specific DNA markers and health-related traits. Because this variant sits in a region involved in immune system regulation, researchers have focused on its potential role in inflammatory conditions. It is important to note that identifying a statistical association does not mean the variant directly causes a disease; rather, it serves as a marker that may be linked to biological pathways involved in immune function.
The Role of the IL2/IL21 Locus
The IL2 and IL21 genes are critical components of the human immune system. Interleukin-2 (IL2) is a cytokine that plays a central role in the activation and regulation of T cells, which are essential for mounting an immune response. It is particularly important for the function of regulatory T cells, which help keep the immune system in check and prevent it from overreacting. Interleukin-21 (IL21) is also involved in the proliferation and maturation of various immune cells. Because these genes are so influential in how the body manages inflammation and immune tolerance, variations in this genomic neighborhood are frequently studied in the context of autoimmune and inflammatory diseases. The interplay between these cytokines and the cells they regulate is complex, and researchers continue to investigate how genetic variations in this region might influence immune system behavior.
Research and Statistical Associations
Large-scale studies, including genome-wide association studies (GWAS), have provided evidence linking rs13151961 to ulcerative colitis. In these studies, researchers compare the frequency of specific alleles in individuals with a condition to those without it. The evidence for this association is considered moderate, as it has been replicated across different cohorts, including European and North American populations. While the statistical significance is strong, the actual effect size—the degree to which the variant increases or decreases risk—is typically modest. This is common in complex traits like inflammatory bowel disease, where hundreds of genetic variants, each with a small effect, interact with environmental factors to influence overall risk. The association is not diagnostic, and the presence of this variant does not guarantee that an individual will develop any specific health condition.
Population Frequency and Interpretation
The rs13151961 variant is commonly observed in European populations. Genetic frequency can vary significantly across different ancestral groups, and what is considered a common variant in one population may be rare in another. When interpreting this information, it is essential to understand that genetic risk is only one piece of a much larger puzzle. Most common diseases are polygenic, meaning they are influenced by many different genes, and they are also heavily impacted by lifestyle, environment, and other non-genetic factors. Because this variant is associated with immune regulation, it is a subject of ongoing scientific interest, but it is not currently used in clinical settings to predict individual health outcomes or to guide medical treatment.
What You Can Do With This Information
Information about genetic variants like rs13151961 is primarily educational and intended to provide insight into the current state of genomic research. It is important to remember that this data cannot be used to diagnose a disease or determine your personal health future. If you have concerns about your health, symptoms of inflammatory bowel disease, or questions about your family medical history, the most appropriate step is to consult with a qualified healthcare professional. They can provide context based on your clinical presentation, physical exams, and other diagnostic tests. Never make changes to your health regimen or medication based on genetic data without first discussing it with your doctor or a licensed pharmacist, as they are the only ones qualified to provide medical advice tailored to your specific needs.
How common is this variant?
The rs13151961 variant is common in European populations, with allele frequencies varying across different global ancestral groups.
Frequently asked questions
Does having the rs13151961 variant mean I will get ulcerative colitis?
No. Having a specific genotype for this variant does not mean you will develop ulcerative colitis. Genetic associations indicate a statistical correlation in large groups of people, not a direct cause for an individual.
Is rs13151961 used for medical testing?
No, this variant is not currently used in clinical diagnostic testing. It is primarily a subject of scientific research into the genetic architecture of inflammatory diseases.
Can I change my risk associated with this gene?
Genetic variants are inherited and cannot be changed. However, health is influenced by many factors, including diet, lifestyle, and environment, which you can discuss with your healthcare provider.
Where can I find more information about IL2 and IBD?
You can explore resources like MedlinePlus Genetics or the GWAS Catalog for general information on how genes and immune function relate to inflammatory bowel disease.
Sources & further reading
Educational information only, last refreshed 10/28/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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