NR1I2 rs12721607: Understanding This Genetic Variant
The rs12721607 variant is a single nucleotide polymorphism located within the NR1I2 gene, which encodes the pregnane X receptor. Research has investigated this variant for potential associations with susceptibility to inflammatory bowel disease and chronic periodontitis.
What each genotype means
Common genetic profile
This is the most common genotype observed for this variant in many populations. Research indicates that the NR1I2 gene, which encodes the pregnane X receptor, plays a role in regulating inflammatory responses, and this specific variant has been studied for potential links to inflammatory bowel disease and chronic periodontitis. Because the evidence for this association is limited, this genotype should be viewed as a standard genetic background rather than a diagnostic indicator.
This is the major homozygous genotype and is found in the vast majority of individuals across global populations.
Variant carrier profile
Carrying one copy of the A allele means you possess a variation within the NR1I2 gene, which acts as a master sensor for xenobiotics and inflammatory signals. Some studies have suggested that specific haplotypes containing this variant may influence susceptibility to inflammatory bowel disease or chronic periodontitis, though the evidence remains limited and mixed. This result does not provide a medical diagnosis, and any concerns regarding inflammatory conditions should be discussed with a healthcare professional.
This heterozygous genotype is relatively uncommon, occurring at a low frequency consistent with the reported global minor allele frequency of approximately 0.6%.
Rare variant profile
This genotype represents the homozygous state for the less common A allele of the NR1I2 gene. While the NR1I2 gene is known to regulate drug metabolism and inflammatory pathways, the clinical significance of this specific genotype regarding disease susceptibility is not well-established. Current research provides limited evidence linking this variant to inflammatory bowel disease or periodontitis, and it is not a predictor of health outcomes.
This genotype is very rare, as the A allele is present at a low frequency in the general population.
What is rs12721607?
The rs12721607 variant is a specific genetic change, or single nucleotide polymorphism (SNP), located on chromosome 3. In the human genome, it sits within the NR1I2 gene, which provides instructions for creating the pregnane X receptor (PXR). A SNP represents a variation at a single position in the DNA sequence, where one nucleotide is replaced by another. Scientists track these variations to understand how they might influence biological processes or disease risk. Because rs12721607 is located within a gene that plays a critical role in how the body processes various substances, it has been a subject of interest in studies looking for links between genetics and chronic inflammatory conditions.
The Role of the NR1I2 Gene
The NR1I2 gene encodes the pregnane X receptor (PXR), a member of the nuclear receptor superfamily of transcription factors. PXR acts as a master regulator in the liver and gastrointestinal tract, where it senses the presence of foreign substances, including medications, toxins, and endogenous steroids. When activated by these compounds, PXR binds to specific DNA sequences to turn on genes involved in the metabolism and excretion of these substances, such as the CYP3A4 enzyme. By facilitating the breakdown and removal of xenobiotics, PXR serves as a vital defense mechanism. Because of its central role in drug metabolism and its expression in the gut, researchers have hypothesized that variations in this gene might influence how the body manages inflammation and immune responses.
Research and Evidence Strength
Scientific literature has explored the potential link between NR1I2 haplotypes—which include rs12721607—and conditions like inflammatory bowel disease (IBD) and chronic periodontitis. While some studies have suggested that certain genetic patterns in this region may modulate susceptibility to these inflammatory conditions, the evidence remains limited. Genetic association studies often face challenges, such as the need for large sample sizes to confirm findings across diverse populations. It is important to note that having a specific genotype does not mean an individual will develop a disease. Many factors, including environment, lifestyle, and other genetic markers, contribute to the development of complex conditions. Current research provides a foundation for understanding these pathways, but the clinical significance of this specific SNP is not yet fully established.
What You Can Do With This Information
Genetic information can be a powerful tool for curiosity and personal learning, but it should not be used to make medical decisions. If you have received results regarding the rs12721607 variant, it is important to view them in the context of your overall health and family history. This variant is not a diagnostic tool for inflammatory bowel disease or any other condition. If you are concerned about your risk for specific health issues, or if you are taking medications that might be affected by PXR activity, please consult with a qualified healthcare provider or a pharmacist. They can help interpret your health status and provide guidance based on established clinical standards rather than individual genetic markers alone.
How common is this variant?
The global minor allele frequency (GMAF) for rs12721607 is approximately 0.005969, indicating that it is a relatively uncommon variant in the general population.
Frequently asked questions
Is rs12721607 a diagnostic test for IBD?
No, rs12721607 is not a diagnostic test for inflammatory bowel disease. Genetic associations are statistical observations in research populations and cannot predict whether an individual will develop a specific disease.
Does this variant affect how my medications work?
The NR1I2 gene regulates enzymes like CYP3A4, which metabolize many drugs. If you are concerned about how your medications are processed, please discuss your genetic results and current prescriptions with your doctor or pharmacist.
Where can I find more information on NR1I2?
You can find authoritative information on the NR1I2 gene through resources like the National Library of Medicine's MedlinePlus Genetics or the UniProt database, which provide detailed summaries of gene function.
Why is the evidence for this variant considered limited?
Evidence is considered limited when initial research findings have not been consistently replicated in large, diverse clinical trials. Further study is often required to confirm the biological impact of a specific SNP.
Sources & further reading
Educational information only, last refreshed 9/20/2026. Not medical advice — these associations describe population statistics, not individual predictions.
Curious what your genotype is for rs12721607?
Upload a raw DNA file from 23andMe, AncestryDNA, MyHeritage, or FamilyTreeDNA and see this variant — plus thousands more — interpreted in your full report.
Get my report — $29