CYP4F3 rs1805042: Understanding This Pharmacogenomic Variant
The rs1805042 variant is a genetic polymorphism located within the CYP4F3 gene, which plays a critical role in the metabolism of various endogenous and exogenous compounds. Research into this variant focuses on its potential influence on how the body processes specific lipids and medications, though its clinical impact remains a subject of ongoing study.
What each genotype means
Typical genotype
This genotype is considered the baseline or reference state for this variant in the CYP4F3 gene. Research has noted that individuals with this genotype may have different susceptibility to certain viral infections compared to those with the G allele, though these findings have not been consistently replicated. As this gene is involved in metabolic processes, you should discuss any concerns regarding medication metabolism or health impacts with your clinician.
This is a common genotype, though its exact frequency varies significantly across different global ancestral populations.
Variant genotype
Carrying one copy of the G allele has been associated in some studies with an increased susceptibility to certain viral infections, such as SARS-CoV-1, when compared to the AA genotype. However, these associations are not definitive and have not been consistently replicated in larger cohorts. Because CYP4F3 plays a role in the metabolism of various compounds, please consult with your pharmacist or physician regarding any implications for your health or medication response.
This heterozygous genotype is found at varying frequencies globally, depending on the specific ancestral background of the population.
Variant genotype
Similar to the AG genotype, the GG genotype has been studied for potential associations with increased susceptibility to certain viral infections compared to the AA genotype. These results remain preliminary and have not been widely replicated across diverse populations. Since this gene is involved in important metabolic pathways, you should discuss any questions about your health or potential medication interactions with a qualified healthcare provider.
This genotype is observed at varying frequencies across different populations and is less common than the reference AA genotype in many groups.
What is the rs1805042 Variant?
The rs1805042 variant is a single nucleotide polymorphism (SNP) situated within the CYP4F3 gene on human chromosome 19. In the context of genomics, a SNP represents a variation at a single position in the DNA sequence among individuals. This specific variant is cataloged in major genetic databases, including dbSNP, which tracks variations to help researchers understand their distribution and potential biological consequences. Because it resides within a gene responsible for enzyme production, scientists investigate whether this change in the genetic code alters the structure or function of the resulting protein. While the presence of this variant is well-documented, its specific functional impact is part of a broader effort to map how individual genetic differences contribute to biological diversity and variations in metabolic efficiency.
The Role of the CYP4F3 Gene
The CYP4F3 gene encodes the CYP4F3 enzyme, a member of the cytochrome P450 superfamily. These enzymes are essential for the oxidation of various organic substances, including drugs, steroids, and lipids. A primary function of the CYP4F3 enzyme is the metabolism of leukotriene B4 (LTB4), which is a potent inflammatory mediator in the human body. By breaking down LTB4, the enzyme helps regulate inflammatory responses. Additionally, CYP4F3 is involved in the metabolism of certain fatty acids, contributing to systemic lipid regulation. The enzyme is expressed in various tissues, with notable activity in the liver and leukocytes. Because of its involvement in both inflammatory pathways and the breakdown of exogenous compounds, variations in this gene are of significant interest to researchers studying how genetic profiles might influence susceptibility to inflammatory conditions or the efficacy of certain therapeutic agents.
Research and Clinical Evidence
Current research into rs1805042 is categorized under pharmacogenomics, the study of how genes affect a person's response to drugs. The evidence strength for this specific variant is currently considered moderate. While studies have explored its association with metabolic processes, it is not yet a standard marker for routine clinical dosing decisions in the same way as more established pharmacogenetic markers. Published literature, including studies found in PubMed, highlights that genetic polymorphisms in CYP4F3 can influence enzyme activity, which may theoretically affect the metabolism of substrates. However, the clinical translation of these findings is still evolving. It is important to note that while associations are observed in research settings, they do not always translate into definitive clinical outcomes. As with all pharmacogenomic data, any questions regarding how your genetic profile might interact with specific medications should be discussed directly with your clinician or a qualified pharmacist.
Population Frequency and Interpretation
The frequency of the rs1805042 variant is known to be variable across different global populations. Genetic databases like gnomAD provide data on how often specific alleles appear in diverse ancestral groups, reflecting the natural variation present in the human genome. Because frequency can differ significantly between populations, researchers must account for ancestry when studying the potential effects of this variant. It is common for many genetic variants to be rare in some groups and more frequent in others, which is a standard observation in human genetics. Understanding these frequency patterns is essential for researchers to avoid bias and ensure that findings are applicable to the populations being studied. For the individual, this variability underscores the importance of viewing genetic information as part of a larger, complex picture of health that includes environmental factors and personal medical history.
What You Can Do With This Information
Accessing information about your genetic variants can be an educational experience, but it is important to maintain a clear perspective on what this data means. You can use this information to engage in more informed conversations with your healthcare provider about your health and potential medication responses. However, you should never use genetic data to make independent medical decisions, such as starting, stopping, or changing the dosage of any medication. Genetic associations are statistical in nature and do not provide a diagnosis or a guaranteed prediction of how your body will react to a specific drug. Always consult with a licensed medical professional who can interpret your genetic results in the context of your overall health, current medications, and clinical needs. Your doctor or pharmacist is the best resource for determining if pharmacogenomic testing is appropriate for your specific situation.
How common is this variant?
The frequency of the rs1805042 variant is variable across different global populations, with specific allele distributions documented in large-scale genomic databases.
Frequently asked questions
Is rs1805042 a diagnostic test for a disease?
No, rs1805042 is not a diagnostic test. It is a genetic variant studied for its potential role in metabolic processes, and it cannot be used to diagnose any medical condition.
Should I change my medication based on this variant?
You should never change your medication or dosage based on genetic information alone. Always consult your doctor or pharmacist before making any changes to your prescribed treatment plan.
Where can I find more information about CYP4F3?
You can find reliable information about the CYP4F3 gene through resources like MedlinePlus Genetics, the NCBI Gene database, and peer-reviewed articles on PubMed.
Why is the evidence for this variant considered moderate?
Evidence is considered moderate because while research shows associations between the variant and metabolic pathways, there is not yet enough definitive clinical data to support widespread, standardized medical guidelines for its use.
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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