TMCO1 rs7555523: What Your Genotype Means
The rs7555523 variant is a common genetic marker located in the TMCO1 gene. It has been identified in research as being associated with variations in intraocular pressure and the risk of developing primary open-angle glaucoma.
What each genotype means
Typical TMCO1 profile
This genotype is associated with lower intraocular pressure compared to the C allele. Research indicates that the TMCO1 gene plays a role in calcium homeostasis and ocular health, and this version is generally considered the lower-risk profile for glaucoma-related pressure changes. As glaucoma is a complex condition, please continue routine eye examinations with your ophthalmologist.
This is the more common genotype in many populations of European descent.
Increased pressure risk
Each copy of the C allele has been statistically associated with a modest increase in intraocular pressure. While this variant is linked to a higher risk of primary open-angle glaucoma in some studies, the effect is influenced by your overall genetic background and other health factors. Please discuss your eye health and the necessity of regular screenings with your eye care professional.
This genotype is found in a significant portion of the population, with frequencies varying by ancestry.
Higher pressure risk
This genotype is associated with a higher statistical risk for elevated intraocular pressure and primary open-angle glaucoma compared to the T allele. Because glaucoma risk is multifactorial, this result does not guarantee the development of the condition, nor does it replace clinical evaluation. You should maintain regular eye health check-ups and discuss this genetic association with your doctor.
This genotype is the least common of the three in many populations, though it is a known risk factor in specific groups.
What is rs7555523?
The rs7555523 variant is a single nucleotide polymorphism (SNP) found within the TMCO1 gene on chromosome 1. In the context of human genetics, this SNP represents a specific point in the DNA sequence where individuals may differ. The TMCO1 gene, or Transmembrane and Coiled-Coil Domains 1, is highly conserved across species and is expressed in various ocular tissues, including the ciliary body, trabecular meshwork, and the retina. These tissues are critical for maintaining the fluid dynamics of the eye. Because of its expression in these areas, researchers have focused on this gene to understand how genetic variations might influence the regulation of intraocular pressure (IOP), which is a primary risk factor for glaucoma. By studying this variant, scientists are working to uncover the biological mechanisms that link genetic architecture to the physical health of the eye.
Association with Eye Health
Research has established a significant association between rs7555523 and intraocular pressure. Genome-wide association studies (GWAS) have consistently identified this variant as a factor that contributes to the normal variance in eye pressure levels. Furthermore, meta-analyses of case-control studies have linked this variant to an increased risk of primary open-angle glaucoma. Some studies suggest that carriers of specific risk alleles at the TMCO1 locus may be predisposed to developing glaucoma with higher intraocular pressure. While the evidence for this association is considered moderate to strong in the context of genetic research, it is important to remember that glaucoma is a multifactorial disease. Genetic markers like rs7555523 provide insight into susceptibility, but they do not act in isolation. Other factors, including age, family history, and overall ocular health, play substantial roles in determining an individual's actual risk profile.
Using Genetic Information
Understanding your genotype for rs7555523 is an educational exercise rather than a diagnostic tool. Because this variant is common in the population, many people carry the alleles associated with higher or lower intraocular pressure without ever developing glaucoma. Genetic data should never be used to self-diagnose or to make decisions about medical treatment. If you are interested in your eye health, the most reliable path is to schedule regular eye examinations with an optometrist or ophthalmologist. These professionals can measure your actual intraocular pressure and assess the health of your optic nerve, which are the standard clinical methods for managing glaucoma risk. If you have a family history of glaucoma or other concerns, discuss these with your clinician, who can provide guidance tailored to your specific health needs and clinical presentation.
How common is this variant?
The rs7555523 variant is considered a common genetic marker, with its allele frequencies varying across different global populations.
Frequently asked questions
What is the TMCO1 gene?
TMCO1 is a gene that encodes a protein involved in calcium homeostasis. It is highly expressed in eye tissues and is a known focus of research regarding glaucoma and intraocular pressure.
Does having the C allele mean I will get glaucoma?
No. Having a specific allele at this location does not mean you will develop glaucoma. It is simply a genetic factor that has been statistically associated with the condition in large population studies.
How is intraocular pressure related to glaucoma?
Intraocular pressure is the fluid pressure inside the eye. Elevated pressure is a major risk factor for primary open-angle glaucoma, which can damage the optic nerve over time.
What should I do if I am worried about glaucoma?
The best course of action is to see an eye care professional for a comprehensive eye exam. They can perform tests to measure your eye pressure and check the health of your optic nerve.
Sources & further reading
Educational information only, last refreshed 11/4/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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