CYP2E1 rs2031920: What Your Genotype Means
The rs2031920 variant is a single nucleotide polymorphism located in the regulatory region of the CYP2E1 gene. It is primarily studied for its potential influence on the activity of the CYP2E1 enzyme, which processes substances such as acetaminophen and ethanol.
What each genotype means
Typical enzyme activity
This is considered the common or wild-type genotype for this variant. Research into this specific marker is ongoing, and while some studies explore its role in metabolic pathways, it is generally associated with standard enzyme function. Please discuss any concerns regarding medication response or metabolic health with your clinician or pharmacist.
This is the most common genotype observed in most studied populations globally.
Heterozygous variant carrier
You carry one copy of the T allele, sometimes referred to in literature as the -1055C>T variant. Some studies have investigated potential associations between this genotype and altered risk for certain cancers or metabolic variations, but results are often mixed or specific to certain populations. Always consult with your healthcare provider regarding your personal health profile and medication management.
Frequency varies significantly by ancestry, appearing in a minority of individuals in many populations but showing higher prevalence in specific regional studies.
Homozygous variant carrier
You carry two copies of the T allele. This genotype is less common than the others and has been the subject of research regarding its influence on the CYP2E1 enzyme's activity and potential disease susceptibility. Because clinical evidence for this variant remains limited and often conflicting, it should not be used to predict specific health outcomes; please discuss any questions with your doctor.
This genotype is rare in many populations and is often absent or found at very low frequencies in many studied cohorts.
Understanding the rs2031920 Variant
The rs2031920 variant is a genetic change located in the 5-prime flanking region of the CYP2E1 gene on chromosome 10. In scientific literature, this position is sometimes referred to as the -1053C>T transition. This specific site is part of a regulatory region that helps control how much of the CYP2E1 enzyme is produced by the body. Because it sits in a regulatory area rather than within the protein-coding sequence itself, it is thought to influence the transcription levels of the gene. Researchers often study this variant in combination with other nearby SNPs, such as rs3813867, to define specific haplotypes like CYP2E1*5B. Understanding where this variant sits is essential for researchers trying to map how genetic architecture affects enzyme expression and, consequently, how individuals might process various chemical substrates.
The Role of the CYP2E1 Enzyme
The CYP2E1 gene encodes a member of the cytochrome P450 superfamily of enzymes. These enzymes are primarily responsible for the metabolism of a wide array of endogenous and exogenous compounds. CYP2E1 is particularly notable for its role in the oxidative metabolism of small molecules, including ethanol, acetone, and certain medications like acetaminophen. Because it is involved in the breakdown of these substances, variations in the gene that alter enzyme levels or activity can theoretically change how quickly or effectively a person processes these compounds. While the enzyme is vital for detoxification, its activity can also lead to the production of reactive intermediates, which is why it is frequently investigated in the context of liver health and drug-induced toxicity. The enzyme's activity is highly dynamic and can be induced by various environmental factors, including alcohol consumption.
Research Associations and Evidence Strength
Research into rs2031920 has explored its association with various health outcomes, including susceptibility to certain cancers and drug-induced liver injury. Some studies have suggested that the variant allele may be linked to altered enzymatic activity, with some reports indicating reduced activity and others suggesting increased transcription when combined with other variants in the *5B haplotype. However, the evidence strength for these associations remains moderate. Results across different studies are often mixed, with some populations showing a clear correlation with disease risk while others show no significant link. This inconsistency is common in pharmacogenomics, as the effect of a single SNP is often modulated by other genetic factors, environmental exposures, and lifestyle choices. Consequently, while rs2031920 is a recognized marker in the field, it is not currently used as a standalone diagnostic tool for predicting clinical outcomes.
What You Can and Cannot Do With This Information
Genetic information regarding variants like rs2031920 is intended for educational and research purposes. It is important to understand that having a specific genotype does not provide a definitive prediction of how your body will react to a medication or your risk for a specific disease. Pharmacogenomic associations are complex and involve many variables beyond a single SNP. You cannot use this information to self-diagnose or make changes to your prescribed medications. If you have concerns about how your genetics might influence your response to a drug, or if you are interested in pharmacogenomic testing, you should discuss this with your clinician or a qualified pharmacist. They can interpret your results within the context of your overall health, medical history, and current treatments to provide personalized guidance that is safe and clinically appropriate.
How common is this variant?
The frequency of the rs2031920 variant is variable across different global populations, with the T allele appearing at different rates in various ethnic groups. It is important to consult population-specific databases like gnomAD for the most accurate frequency data relevant to specific ancestries.
Frequently asked questions
Is rs2031920 a diagnostic test for drug reactions?
No, rs2031920 is not a diagnostic test. While it is studied in pharmacogenomics, it is not used in clinical practice to predict individual drug reactions or to guide dosing decisions.
Does this variant mean I have a liver problem?
No, having a specific genotype at rs2031920 does not mean you have a liver disease. It is simply a genetic variation that may influence how your body processes certain substances.
Should I change my medication based on my rs2031920 result?
You should never change your medication based on genetic test results without consulting your doctor. Always speak with your healthcare provider before making any changes to your treatment plan.
Where can I find more information about CYP2E1?
You can find reliable information about the CYP2E1 gene and its variants on resources like MedlinePlus Genetics, the PharmGKB database, and the NCBI Gene database.
Sources & further reading
Educational information only, last refreshed 9/30/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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A genetic marker associated with CYP2E1 enzyme function, which plays a key role in the metabolism of xenobiotics and endogenous compounds.
Regulatory promoter variant in CYP2E1 (c.-1055C>T, defining CYP2E1*5B) linked to altered transcriptional induction and variable metabolism of acetaminophen, ethanol, and volatile anesthetics.