TTC6 rs1998359: Understanding Your Genetic Association with Allergy
The genetic variant rs1998359 is a single nucleotide polymorphism (SNP) located near the TTC6 gene on chromosome 14. It has been identified in large-scale genome-wide association studies as having a statistical link to self-reported allergic conditions.
What each genotype means
Typical allergy risk profile
This genotype represents the non-risk version of the variant associated with self-reported allergy. Research indicates that individuals with this profile do not carry the specific genetic marker linked to increased susceptibility in genome-wide association studies.
This is the most common genotype, found in the majority of the population across most ancestries.
Slightly elevated allergy risk
Carrying one copy of the G allele is associated with a statistically higher likelihood of self-reported allergy compared to those without the allele. This association is based on large-scale meta-analyses, though individual risk is influenced by many other genetic and environmental factors.
Carried by a significant portion of the population, consistent with the reported minor allele frequency of approximately 0.1749.
Increased allergy risk profile
This genotype is identified as the risk-associated profile in genome-wide association studies regarding self-reported allergy. While this marker is statistically linked to the trait, it is not a diagnostic tool and does not guarantee the development of allergies.
This is the least common genotype, occurring in a smaller subset of the population consistent with the reported minor allele frequency.
What is rs1998359 and Where is it Located?
The variant rs1998359 is a specific position in the human genome where individuals may differ by a single DNA letter. It is situated on chromosome 14 at position 14q21.1. In genomic studies, this location is noted for its proximity to two genes: FOXA1 and TTC6. Because SNPs are often used as signposts in the genome, researchers look at this specific site to see if it correlates with certain physical traits or health conditions. When a SNP is found to be associated with a trait, it does not necessarily mean the SNP itself causes the trait; rather, it may be inherited alongside other functional genetic changes in the nearby region that influence biological processes.
The Role of the TTC6 Gene
The TTC6 gene, or Tetratricopeptide Repeat Domain 6, provides instructions for making a protein that contains tetratricopeptide repeat motifs. These motifs are structural patterns often involved in protein-protein interactions, which are essential for various cellular functions. While the exact biological mechanism linking TTC6 to immune responses is still being investigated, some research suggests that genes in this family may be involved in ciliary assembly and function. In the context of the 14q21.1 region, researchers are interested in how the local genetic environment might influence immune system regulation. It is important to note that genetic associations are complex, and the presence of a variant near a gene does not automatically imply that the gene is the primary driver of a specific clinical condition.
Evidence and Research Associations
The association between rs1998359 and allergy was highlighted in a large-scale genome-wide association meta-analysis involving over 50,000 individuals. This study sought to identify genetic loci shared across different types of self-reported allergies, such as those to cats, dust mites, and pollen. The researchers found that rs1998359 reached a level of statistical significance that warranted its inclusion as a susceptibility locus. The evidence for this association is considered moderate, as it reflects a statistical correlation observed in a large population rather than a direct, deterministic cause of disease. Because allergy is a multifactorial trait influenced by both genetics and environmental exposures, this SNP represents only a small piece of a much larger, complex puzzle regarding how the immune system reacts to allergens.
Understanding Your Results
If you have information about your genotype at rs1998359, it is important to view it as a statistical observation rather than a medical diagnosis. Genetic associations identified in research studies describe trends across large groups of people and cannot predict individual health outcomes. Many factors, including your environment, lifestyle, and the rest of your genetic makeup, play a much larger role in whether you develop allergies. You cannot use this information to diagnose yourself or to determine the severity of any potential allergic response. If you have concerns about allergies or your immune health, the most appropriate step is to consult with a healthcare professional or an allergist. They can provide personalized guidance based on your clinical history and symptoms, which are far more informative than any single genetic variant.
How common is this variant?
The variant rs1998359 is relatively common, with a reported population frequency of approximately 0.1749 for the minor allele in certain study cohorts.
Frequently asked questions
Does having this variant mean I will have allergies?
No, having this variant does not mean you will have allergies. Genetic associations are statistical, meaning they show a slight increase in the likelihood of a trait across a large group, but they do not determine individual health outcomes.
Can I use this SNP to test for allergy severity?
No, this SNP cannot be used to test for or predict the severity of allergies. Allergy severity is influenced by a wide range of complex factors, including your environment and overall immune system function.
What should I do if I am worried about my allergy risk?
If you are concerned about allergies, you should speak with a doctor or an allergist. They can perform clinical tests and evaluate your symptoms to provide an accurate assessment of your health.
Is the TTC6 gene the only thing that causes allergies?
Allergies are complex, multifactorial conditions influenced by many different genes and environmental factors. No single gene is responsible for causing allergies in all people.
Sources & further reading
Educational information only, last refreshed 10/17/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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