CDC42EP3 rs8135665: What Your Genotype Means
The genetic variant rs8135665 is a single nucleotide polymorphism (SNP) located within the CDC42EP3 gene. It has been identified in scientific studies as being statistically associated with variations in optic disc morphology and the vertical cup-to-disc ratio.
What each genotype means
Typical optic disc morphology
This genotype represents the major allele configuration for this variant. Research indicates this variant is associated with variations in optic disc morphology and the vertical cup-to-disc ratio, though the clinical significance of these associations remains limited. This profile is considered the baseline in populations where the A allele is more prevalent.
This genotype is common in many populations, reflecting the high frequency of the A allele.
Varied optic disc morphology
Carrying one copy of the G allele may be associated with subtle differences in optic disc measurements compared to those without the variant. Because the evidence linking this specific SNP to optic nerve head traits is limited, these findings should not be used for clinical diagnosis or predicting eye health outcomes.
This heterozygous genotype is frequently observed, consistent with the reported minor allele frequency of approximately 0.45 in European populations.
Distinct optic disc morphology
This genotype contains two copies of the minor allele associated with studies on optic disc and cup area morphology. While statistical associations have been identified in large-scale genomic studies, the functional impact on individual eye health is not well-defined and remains a subject of ongoing research.
This genotype is carried by a significant portion of the population, occurring in roughly 1 in 5 individuals of European ancestry.
Understanding rs8135665
A single nucleotide polymorphism, or SNP, is a variation at a single position in a DNA sequence among individuals. The variant rs8135665 is located within the CDC42EP3 gene, which stands for CDC42 effector protein 3. In the context of human genetics, researchers use SNPs like rs8135665 as markers to study how specific regions of the genome might influence physical traits or susceptibility to certain conditions. This particular variant is cataloged in public databases that track findings from genome-wide association studies (GWAS). These studies compare the DNA of large groups of people to identify statistical correlations between specific genetic markers and observable characteristics. It is important to note that a statistical association does not necessarily imply a direct cause-and-effect relationship between the variant and a specific health outcome.
The Role of CDC42EP3
The CDC42EP3 gene encodes a protein that belongs to a family of proteins known to interact with CDC42, a small GTPase involved in regulating the cytoskeleton. By influencing the structure and organization of the cell's internal framework, these proteins play roles in various cellular processes, including cell shape, movement, and division. While the exact biological mechanisms linking CDC42EP3 to ocular structures are still being investigated, the gene's involvement in cytoskeletal dynamics provides a plausible area for research into how it might influence the development or maintenance of tissues in the eye. Current scientific literature focuses on how variations in such genes might contribute to the structural diversity of the optic nerve head, which is a critical component of the eye's anatomy and a subject of interest in ophthalmological research.
Research and Evidence Strength
The association between rs8135665 and optic disc morphology, specifically the vertical cup-to-disc ratio, is based on findings from large-scale genetic studies. The vertical cup-to-disc ratio is a clinical measurement used by eye care professionals to assess the health of the optic nerve, particularly in the context of glaucoma management. While GWAS have identified this SNP as having a statistical link to these ocular parameters, the evidence strength is currently considered limited. This means that while the correlation has been observed in research cohorts, it does not serve as a diagnostic tool or a definitive predictor of eye health. Genetic associations are often complex, involving many different genes and environmental factors, and the findings for rs8135665 represent a small piece of a much larger, ongoing puzzle in human genetics.
Population Frequency and Interpretation
Genetic variants are distributed differently across various human populations, and understanding these frequencies is essential for interpreting genomic data. For rs8135665, the minor allele frequency is approximately 0.45 in European populations. This indicates that the variant is relatively common in this demographic. When interpreting such data, it is crucial to recognize that frequency does not equate to clinical significance. Having a common variant is a normal part of human genetic diversity. Because the evidence linking this SNP to specific traits is limited, individuals should not use this information to make assumptions about their personal health or risk for eye diseases. Genetic data is best understood in the context of a comprehensive clinical evaluation by a qualified healthcare provider who can consider family history, lifestyle, and other relevant medical factors.
How common is this variant?
The minor allele frequency for rs8135665 is approximately 0.45 in European populations, making it a relatively common variant.
Frequently asked questions
Can this SNP predict if I will get glaucoma?
No, this SNP cannot predict if you will develop glaucoma. While it is associated with optic disc measurements, these measurements are only one factor in a complex clinical assessment, and the evidence for this specific variant is limited.
Should I be worried if I have the 'risk' allele?
There is no 'risk' allele in the sense of a disease-causing mutation. This variant is simply a common genetic difference that has been statistically linked to variations in eye anatomy in research studies.
What is the vertical cup-to-disc ratio?
The vertical cup-to-disc ratio is a measurement used by eye doctors to describe the appearance of the optic nerve head. It compares the size of the central 'cup' of the optic disc to the total size of the disc itself.
Where can I learn more about my eye health?
The best way to learn about your eye health is to schedule a comprehensive eye exam with an optometrist or ophthalmologist. They can provide personalized information based on your actual clinical findings rather than genetic markers.
Sources & further reading
Educational information only, last refreshed 9/16/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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