RDH5 rs3138141: Understanding This Genetic Variant
The rs3138141 variant is a genetic marker located within the RDH5 gene region. Research has identified this variant as being linked to the regulation of RDH5 expression, which is critical for the visual cycle in the eye.
What each genotype means
Typical RDH5 function
This genotype represents the most common sequence found in the RDH5 gene. Individuals with this profile are expected to have normal 11-cis retinol dehydrogenase activity, which is essential for the visual cycle and proper dark adaptation.
This is the most common genotype observed across all global populations.
Carrier of variant allele
You carry one copy of the variant allele and one copy of the common allele. Because conditions associated with RDH5 variants are typically inherited in an autosomal recessive pattern, carriers generally do not exhibit the clinical features of fundus albipunctatus.
This genotype is found at a low frequency, consistent with the minor allele frequency of less than 0.02 globally.
Potential visual cycle impact
This genotype indicates two copies of the variant allele, which may be associated with altered 11-cis retinol dehydrogenase activity. Research links RDH5 variants to fundus albipunctatus, a condition characterized by delayed dark adaptation and white retinal spots; please consult with an ophthalmologist or genetic counselor to discuss your specific clinical context.
This genotype is rare, occurring in a very small fraction of the population globally.
What is rs3138141 and Where is it Located?
The variant rs3138141 is a single nucleotide polymorphism (SNP) situated in the genomic region of the RDH5 gene on chromosome 12. In the context of human genetics, SNPs are the most common type of genetic variation, representing a difference in a single DNA building block, or nucleotide. This specific variant has been identified in scientific literature as being tightly linked to another variant, rs3138142. Together, these markers have been studied for their potential influence on the expression levels of the RDH5 gene. Because this variant is located in a regulatory region, researchers investigate whether it affects how much of the RDH5 protein is produced in the retinal pigment epithelium, a layer of cells essential for maintaining healthy vision.
The Role of the RDH5 Gene
The RDH5 gene provides the blueprint for an enzyme known as 11-cis retinol dehydrogenase 5. This enzyme is a vital component of the visual cycle, a complex biochemical process that occurs in the retinal pigment epithelium at the back of the eye. The primary function of this enzyme is to convert all-trans retinal back into 11-cis retinal, which is the universal chromophore required for visual pigments to detect light. When this cycle functions correctly, the eyes can effectively process light into electrical signals that the brain interprets as vision. Mutations that cause a loss of function in the RDH5 gene are well-documented as the cause of autosomal recessive fundus albipunctatus, a condition characterized by night blindness and a delayed regeneration of photopigments.
Research Associations and Evidence Strength
The evidence linking rs3138141 to specific clinical outcomes is currently considered limited. While some studies have explored the potential role of the RDH5 gene region in age-related macular degeneration (AMD), the functional impact of the rs3138141 variant itself remains a subject of ongoing investigation. It is important to distinguish between rare, pathogenic mutations in RDH5 that cause clear clinical conditions like fundus albipunctatus and common variants like rs3138141, which may only subtly influence gene expression. Current research suggests that while this variant is correlated with RDH5 expression levels, it does not necessarily indicate the presence of a disease. As with many genetic markers identified in large-scale genomic studies, the clinical significance of this specific SNP is not yet fully established, and it should not be used to predict individual health outcomes.
Population Frequency
The rs3138141 variant is found across various global populations, though its frequency can vary significantly depending on ancestral background. Generally, the minor allele frequency for this variant is reported to be less than 0.02 globally. This low frequency indicates that the variant is relatively uncommon in the general population. Because genetic diversity is high, individuals may carry different versions of this SNP depending on their heritage. Large-scale databases like gnomAD provide data on how often this variant appears in different ethnic groups, helping researchers understand its distribution. However, because the frequency is low, it is often categorized as a rare or infrequent variant in many study cohorts.
What You Can and Cannot Do With This Information
Understanding your genetic data can be an educational experience, but it is vital to maintain realistic expectations regarding what this information means for your health. You can use this information to learn more about the biological processes, such as the visual cycle, that keep your eyes functioning. However, you cannot use the presence of the rs3138141 variant to diagnose yourself with any eye condition or to predict future vision loss. Genetic variants often require complex interactions with other genes and environmental factors to manifest any physical effect. If you have concerns about your vision, such as difficulty seeing in low light or changes in your field of vision, the most appropriate step is to consult with an ophthalmologist or optometrist. They can perform clinical exams that are far more diagnostic than any genetic test for common variants.
How common is this variant?
The rs3138141 variant is relatively rare, with a global minor allele frequency of less than 0.02 across most studied populations.
Frequently asked questions
Is rs3138141 a cause of blindness?
No, rs3138141 is a common genetic variant and is not considered a cause of blindness. While the RDH5 gene is associated with rare, inherited retinal conditions, this specific SNP is not a known pathogenic mutation.
Should I be worried if I have the G allele?
There is no reason for concern based on this variant alone. Genetic variants are a normal part of human diversity, and most do not have a significant impact on your health or daily life.
Can this variant predict my risk for macular degeneration?
Current research has not established a strong or clinically actionable link between rs3138141 and the risk of developing age-related macular degeneration. Genetic risk for complex eye conditions is usually determined by many factors, not a single SNP.
Where can I find more information about my eye health?
For reliable information regarding your eye health, you should visit the American Academy of Ophthalmology or consult with a licensed eye care professional. They can provide personalized advice based on your medical history and clinical examinations.
Sources & further reading
Educational information only, last refreshed 9/27/2026. Not medical advice — these associations describe population statistics, not individual predictions.
Curious what your genotype is for rs3138141?
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 RDH5
Coding variant in 11-cis retinol dehydrogenase 5 modulating enzymatic recycling of rhodopsin in the retinal visual cycle.
Intronic locus associated with quantitative measures of refractive error and visual acuity across multi-ethnic vision studies.