TF Gene Variant rs8177240: Understanding Iron Metabolism Markers
The rs8177240 variant is a common genetic change located within the transferrin (TF) gene. It has been identified in scientific research as being associated with variations in circulating transferrin levels and other biomarkers related to systemic iron status.
What each genotype means
Typical transferrin levels
You carry two copies of the common C allele at rs8177240 in the TF gene. Research associates this baseline genotype with typical circulating levels of serum transferrin and standard total iron-binding capacity. Because these findings represent broad population associations rather than diagnostic markers, this genotype does not indicate clinical iron deficiency or iron overload on its own.
Carried by approximately 50% to 65% of individuals globally, making it the most frequent genotype across major ancestral populations.
Moderately altered transferrin levels
You carry one copy of the T allele at rs8177240, an intronic variant in the transferrin (TF) gene. Large genome-wide association studies show that each copy of the T allele is associated with a modest decrease in circulating transferrin concentration and altered iron biomarker measurements. This genetic tendency contributes only a small fraction of the variation in overall iron homeostasis and does not constitute a diagnosis of anemia or iron imbalance.
Carried by roughly 30% to 40% of people across European, American, and Asian populations.
Lower transferrin levels
You carry two copies of the T allele at rs8177240 in the TF gene. Genome-wide studies correlate this genotype with significantly lower circulating serum transferrin levels and lower total iron-binding capacity compared to the reference genotype. Evidence for broader clinical health consequences remains limited, and routine clinical laboratory tests are necessary to assess your actual functional iron status.
Found in approximately 3% to 9% of individuals worldwide, depending on specific ancestral background.
What is rs8177240?
The rs8177240 variant is a single nucleotide polymorphism (SNP) located within the TF gene, which resides on chromosome 3. Specifically, this variant is situated within the intronic regions of the gene, which are segments of DNA that do not code for proteins but can influence how genes are regulated or expressed. In the context of genetic research, rs8177240 is often studied alongside other variants in the same genomic region to understand how inherited differences contribute to the diversity of physiological traits in humans. Because it is located in a non-coding region, its exact biological mechanism—how it might influence the production or function of the transferrin protein—remains a subject of ongoing investigation. Researchers use such SNPs as markers to track how specific segments of DNA are inherited and to identify statistical links between these segments and measurable health-related traits.
The Role of the TF Gene
The TF gene provides instructions for making a protein called transferrin. Transferrin is a glycoprotein found in blood plasma that plays a critical role in iron metabolism. Its primary function is to bind to iron and transport it through the bloodstream to various tissues and organs, including the bone marrow, where it is used to produce hemoglobin for red blood cells. By binding free iron, transferrin also helps prevent the potential toxicity that can occur when iron levels are too high or unregulated. The regulation of transferrin is essential for maintaining iron homeostasis, ensuring that the body has enough iron for vital processes while avoiding the damage associated with iron overload. Because iron is a necessary component for many biological functions, the TF gene is a central focus in studies examining how genetic variation influences iron-related health markers.
Research Associations and Evidence
Scientific research, including genome-wide association studies (GWAS), has identified rs8177240 as being associated with markers of iron status, such as circulating transferrin levels. While these statistical associations are documented in the literature, the evidence strength for this specific variant is generally considered limited. This means that while a correlation has been observed in large population studies, the variant is not necessarily a direct cause of clinical iron disorders. Instead, it may act as a modifier or a marker that is inherited alongside other functional changes. It is important to note that iron status is a complex trait influenced by a combination of genetic factors, diet, and environmental exposures. Consequently, the presence of this variant does not provide a definitive prediction of an individual's iron levels or health status, and it should not be used for diagnostic purposes.
Population Frequency
The rs8177240 variant is considered common across various global populations. Research indicates that the minor allele frequency for this SNP typically ranges between approximately 0.15 and 0.30. This frequency is observed consistently across European populations as well as other diverse ancestral groups. Because it is a common variant, a significant portion of the general population carries at least one copy of the minor allele. The widespread nature of this variant suggests that it is a normal part of human genetic diversity rather than a rare mutation associated with a specific disease. Understanding its prevalence helps researchers contextualize its role in population-level studies of iron metabolism, as common variants often have smaller individual effects on physiological traits compared to rare, high-impact mutations.
Interpreting Your Genetic Information
Information regarding genetic variants like rs8177240 is intended for educational purposes and should not be used to make medical decisions. Because the association between this variant and iron status is based on statistical trends in large groups, it cannot predict the specific iron levels or health outcomes for any single individual. If you are concerned about your iron levels, such as symptoms of iron deficiency or iron overload, it is essential to consult with a healthcare professional. A doctor can order standard clinical blood tests, such as serum ferritin or transferrin saturation, which provide a direct and accurate assessment of your iron status. Never attempt to adjust your diet or take iron supplements based on genetic data alone, as improper iron supplementation can be harmful. Always discuss any health concerns or questions about your genetic results with a qualified clinician or a registered dietitian.
How common is this variant?
The rs8177240 variant is common across European and global populations, with a minor allele frequency of approximately 0.15 to 0.30.
Frequently asked questions
Does having the rs8177240 variant mean I have an iron disorder?
No. This variant is associated with normal variations in iron biomarkers and is not a diagnostic marker for iron-related diseases like hemochromatosis or anemia.
Should I change my diet based on my rs8177240 genotype?
You should not change your diet based on this genetic information. If you have concerns about your iron intake, consult a doctor or dietitian to determine if testing is necessary.
Is rs8177240 the same as the HFE gene mutations?
No. The TF gene and the HFE gene are different genes located on different chromosomes. HFE mutations are the primary cause of hereditary hemochromatosis.
Where can I get my iron levels tested?
You can request iron status blood tests, such as serum ferritin or transferrin saturation, from your primary care physician. These tests provide a direct measurement of your body's iron levels.
Sources & further reading
Educational information only, last refreshed 10/12/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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