SLCO1B1 rs2306283: What Your Genotype Means
The rs2306283 variant is a common genetic change in the SLCO1B1 gene, which encodes a protein responsible for transporting medications into the liver. This variant is associated with altered transporter activity, which can influence how the body processes and clears certain statin medications.
What each genotype means
Normal transporter activity
This genotype is often associated with the SLCO1B1*1a haplotype, which represents the reference function for the OATP1B1 transporter. Research suggests this genotype does not contribute to the increased risk of statin-induced myopathy often linked to other SLCO1B1 variants. Please discuss your medication management and any muscle-related symptoms with your healthcare provider.
The A allele is common, and the AA genotype is found frequently across global populations.
Increased transporter activity
The G allele at this position is part of the SLCO1B1*1b haplotype, which may be associated with increased OATP1B1 transporter function compared to the reference. Some studies suggest this variant may have a protective effect against statin-induced myopathy, though clinical evidence remains limited. Always consult your clinician or pharmacist regarding your specific statin therapy and dosing.
This is a very common genotype, with the G allele appearing in approximately 44% of individuals in some European-ancestry cohorts.
Enhanced transporter activity
Carrying two copies of the G allele is associated with the SLCO1B1*1b haplotype, which may enhance hepatic uptake of certain medications. While some research indicates this may be associated with a lower risk of statin-induced muscle side effects, the clinical impact is considered minor. Please consult your healthcare provider to determine if this information is relevant to your current treatment plan.
This genotype is common worldwide, reflecting the high prevalence of the G allele in many global populations.
Understanding the rs2306283 Variant
The rs2306283 variant is a single-nucleotide polymorphism (SNP) located within the SLCO1B1 gene on chromosome 12. In scientific literature, this variant is frequently referred to as c.388A>G, representing a change where the nucleotide adenine is replaced by guanine. This specific alteration results in a nonsynonymous change in the protein sequence, specifically p.Asn130Asp. Because this variant is common across many global populations, it has been extensively studied in the context of pharmacogenomics—the field that examines how genetic variations influence an individual's response to drugs. It is often analyzed alongside other variants in the same gene, such as rs4149056, to understand the complex landscape of how our DNA affects the way we metabolize and clear therapeutic agents from our bloodstream.
The Role of the SLCO1B1 Gene
The SLCO1B1 gene provides instructions for making a protein called organic anion-transporting polypeptide 1B1 (OATP1B1). This protein is primarily expressed in the liver, where it acts as a gatekeeper, facilitating the uptake of various substances from the blood into liver cells. This process is critical for the metabolism and eventual clearance of many medications, including statins, which are widely prescribed to lower cholesterol levels. When the OATP1B1 transporter functions efficiently, it helps move statins into the liver, where they can exert their therapeutic effects. Variations in the SLCO1B1 gene can change the structure or expression levels of this transporter, potentially altering the rate at which these drugs are cleared from the body. Consequently, these genetic differences can lead to variations in drug concentration in the blood, which may influence both the efficacy of the treatment and the risk of side effects.
Research Associations and Evidence
Research into rs2306283 has primarily focused on its impact on statin pharmacokinetics. Some studies suggest that the G allele of rs2306283 may be associated with increased transporter activity, which could lead to lower systemic concentrations of certain statins. Conversely, other research has explored how this variant interacts with other SLCO1B1 polymorphisms to modulate the risk of statin-induced myopathy, a condition characterized by muscle pain or weakness. It is important to note that the evidence regarding the clinical impact of rs2306283 alone is considered limited. While some studies have observed associations with drug clearance rates, the clinical significance can be mixed and may depend on the specific type of statin being used, as well as the presence of other genetic variants. Because of this complexity, the findings are generally used to support broader research rather than to dictate specific clinical dosing decisions in isolation.
Navigating Your Genetic Information
If you have received information about your rs2306283 genotype, it is essential to interpret it within the context of your overall health and current medical treatments. This variant is a common genetic feature and does not, by itself, indicate a health condition or a guaranteed response to any medication. Pharmacogenomic research is an evolving field, and associations between specific SNPs and drug responses are often influenced by many factors, including diet, lifestyle, other medications, and additional genetic markers. You should never use genetic information to make changes to your prescribed medications or dosing schedules. If you are concerned about how your genetics might influence your response to a statin or any other drug, the most appropriate step is to discuss this information with your healthcare provider or a clinical pharmacist. They can evaluate your genetic results alongside your clinical history to provide personalized guidance.
How common is this variant?
The rs2306283 variant is highly common, with a minor allele frequency (MAF) typically ranging between 0.35 and 0.50 across diverse global populations.
Frequently asked questions
What does the rs2306283 variant do?
The rs2306283 variant is a genetic change in the SLCO1B1 gene that may influence the activity of the OATP1B1 transporter protein. This protein helps move certain medications, such as statins, from the blood into the liver for processing.
Does this variant mean I will have side effects from statins?
No, having this variant does not guarantee that you will experience side effects. While some research explores links between SLCO1B1 variants and statin-related muscle symptoms, many factors influence drug response, and the evidence for this specific SNP is limited.
Should I change my medication based on this result?
You should never change your medication or dosage based on genetic test results without consulting your doctor. Always speak with your healthcare provider or a pharmacist to discuss how your genetic information relates to your specific treatment plan.
Is rs2306283 the same as the SLCO1B1*5 variant?
No, they are different. rs2306283 is often referred to as the c.388A>G variant, while other variants like rs4149056 (c.521T>C) are associated with different star allele designations, such as *5 or *15.
Sources & further reading
Educational information only, last refreshed 9/21/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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This missense variant (p.Pro155Thr) is associated with reduced OATP1B1 transporter function, which can lead to increased plasma concentrations of certain statins and higher risk of myopathy.
A regulatory variant in the SLCO1B1 gene influencing statin pharmacokinetics.
Defines the c.388A>G (p.Asn130Asp) variant, which is a component of the SLCO1B1*1B and *15 haplotypes, influencing hepatic statin uptake.
Non-synonymous coding polymorphism (p.Asn130Asp) defining the SLCO1B1*30 allele with modest alteration in hepatic statin uptake.
This variant (c.521T>C) is strongly associated with decreased function of the OATP1B1 transporter, significantly increasing the risk of statin-induced myopathy.
Defines the SLCO1B1*14 haplotype (p.Gly488Ala) associated with altered hepatic uptake transporter activity and statin pharmacokinetics.