TAS2R38 rs17267440: What Your Genotype Means
The rs17267440 variant is a functional genetic marker located within the TAS2R38 gene, which encodes a receptor responsible for detecting bitter compounds. This variant is widely studied for its role in determining an individual's sensitivity to bitter tastes, such as those found in phenylthiocarbamide (PTC) and propylthiouracil (PROP).
What each genotype means
High bitter sensitivity
You carry two copies of the C allele, which encodes alanine at position 262 (A262) and is strongly linked to the functional taster form of the TAS2R38 receptor, commonly designated as the PAV haplotype. Research associates this genotype with an increased sensitivity to the bitter taste of compounds such as phenylthiocarbamide (PTC), propylthiouracil (PROP), and certain cruciferous vegetables. While this trait primarily influences dietary taste preferences, if you take medications that have a strong bitter flavor or narrow therapeutic windows, discuss any administration concerns with your doctor or pharmacist.
Found in approximately 30% to 35% of individuals globally, though frequencies vary depending on ancestral background.
Intermediate bitter sensitivity
You carry one copy of the C allele and one copy of the T allele, corresponding to a heterozygous genotype encoding both alanine and valine at residue 262. In population studies, individuals with this genotype typically exhibit intermediate taste sensitivity to bitter thiourea compounds, distinguishing bitterness at lower thresholds than non-tasters but higher thresholds than homozygous tasters. This is a benign sensory trait that can shape vegetable and food preferences, and any bitter medication concerns should be discussed with a healthcare provider.
Carried by approximately 45% to 50% of people globally due to balanced selection maintaining both alleles across populations.
Reduced bitter sensitivity
You carry two copies of the T allele, which encodes valine at position 262 (V262) and commonly forms part of the non-taster AVI haplotype. Research indicates that this genotype is linked to significantly reduced or absent sensitivity to the bitterness of synthetic thioureas like PTC and PROP, as well as glucosinolates found in brassica vegetables. This is a common, normal variation in taste perception that does not indicate a medical condition, though you should always consult your pharmacist or clinician if you experience medication-related side effects or taste aversions.
Present in roughly 15% to 20% of people worldwide, being common across European, Asian, and African ancestries.
Understanding the SNP and the TAS2R38 Gene
The rs17267440 variant is a single nucleotide polymorphism (SNP) situated within the TAS2R38 gene. This gene provides instructions for creating a G protein-coupled receptor found on the surface of taste receptor cells on the tongue. This specific receptor is specialized to detect glucosinolates, a family of bitter-tasting compounds commonly found in cruciferous vegetables like broccoli and Brussels sprouts. By acting as a chemical sensor, the TAS2R38 receptor allows the brain to perceive bitterness, which historically served as an evolutionary warning system to avoid potentially toxic substances in the environment. Because this gene is highly polymorphic, small changes in its DNA sequence can lead to significant differences in how individuals perceive the intensity of bitter flavors, effectively creating a spectrum of 'taster' and 'nontaster' phenotypes across the human population.
Research Associations and Evidence Strength
Research into TAS2R38 has primarily focused on its influence on taste perception. Individuals carrying specific alleles are often categorized as 'tasters' or 'nontasters' based on their sensitivity to compounds like PROP and PTC. Beyond taste, recent scientific interest has expanded to include potential links between these genotypes and broader health outcomes. Some studies suggest associations between TAS2R38 variants and behavioral traits, such as alcohol intake and smoking habits, potentially because bitter taste sensitivity influences food and beverage preferences. Furthermore, emerging research has identified the TAS2R38 receptor in intestinal cells, where it may play a role in secreting hormones like GLP-1 that help regulate blood sugar. While these findings are intriguing, the evidence linking this specific SNP to clinical health outcomes remains limited. Most associations are statistical in nature, and researchers emphasize that individual taste perception is complex and influenced by both genetics and environmental factors like age.
What You Can and Cannot Do With This Information
Understanding your genotype for rs17267440 can provide insight into why you might find certain foods, such as dark leafy greens or coffee, more intensely bitter than others do. It is a fascinating look at the biological basis of sensory perception. However, it is important to recognize the limitations of this information. This genetic variant is not a diagnostic tool for any medical condition, nor should it be used to make dietary or lifestyle changes without professional guidance. While some studies explore links between taste receptors and metabolic health, these are population-level observations and do not predict individual health outcomes. If you are concerned about your diet, blood glucose levels, or metabolic health, you should consult with a registered dietitian or a healthcare provider. They can provide personalized advice based on your overall health history rather than a single genetic marker.
How common is this variant?
The rs17267440 variant is common globally, with a minor allele frequency typically ranging between 0.40 and 0.45 across diverse ancestral populations.
Frequently asked questions
Does my TAS2R38 genotype mean I am a supertaster?
While TAS2R38 variants influence bitter taste sensitivity, the term 'supertaster' is a specific clinical phenotype that involves more than just this gene. Your genotype provides information about your sensitivity to specific compounds like PROP, but it does not define your entire sensory experience.
Can this gene predict if I will develop diabetes?
No. While recent research suggests a potential link between TAS2R38 and glucose regulation, this is an area of ongoing study. This variant is not a diagnostic marker for diabetes, and you should rely on standard clinical screenings for your metabolic health.
Why do I like vegetables that others find bitter?
Taste perception is highly individual and influenced by your genetics, age, and past experiences. If you enjoy bitter vegetables despite having a 'taster' genotype, it may be due to your personal dietary habits or the way your brain has learned to interpret those flavors over time.
Does this variant affect my medication choices?
There is no current clinical evidence suggesting that this variant should dictate your medication choices. Always discuss any concerns regarding your prescriptions or potential side effects with your doctor or pharmacist.
Sources & further reading
Educational information only, last refreshed 10/18/2026. Not medical advice — these associations describe population statistics, not individual predictions.
Curious what your genotype is for rs17267440?
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 — $29Related variants in TAS2R38
A functional variant in the TAS2R38 gene that, as part of a three-SNP haplotype, determines the ability to taste bitter compounds like PTC.
Val262Ala substitution in TAS2R38 forming the middle polymorphic site of the classic AVI/PAV taste sensitivity haplotype.
One of the three classical missense variants defining the PAV bitter taster haplotype for phenylthiocarbamide and cruciferous vegetables.
Key missense polymorphism contributing to phenylthiocarbamide (PTC) and propylthiouracil (PROP) bitter taste taster status.
Functional marker affecting bitter taste perception of phenylthiocarbamide (PTC).
A key SNP in the TAS2R38 gene (part of the PAV/AVI haplotype) determining sensitivity to bitter compounds like PTC and PROP.