CYP1B1 rs104894468: Understanding a Rare Ocular Variant
The genetic variant rs104894468 is a rare alteration in the CYP1B1 gene that results in an amino acid substitution. It is associated with an increased risk for primary congenital and juvenile glaucoma due to its role in ocular development.
What each genotype means
Typical CYP1B1 function
This genotype represents the most common sequence at this position in the CYP1B1 gene. It is considered the reference or wild-type state, and individuals with this genotype do not carry the specific Arg368His substitution associated with primary congenital glaucoma.
This is the most common genotype observed globally across all major ancestral populations.
Carrier of variant allele
This genotype indicates the presence of one copy of the Arg368His (R368H) variant. While this variant is linked to an increased risk of primary congenital and juvenile glaucoma, the condition typically follows an autosomal recessive inheritance pattern, meaning carriers are often asymptomatic. You should discuss any concerns regarding ocular health or family history with an ophthalmologist.
This genotype is rare, with the variant allele observed at a global frequency of less than 0.0001 in the gnomAD database.
Increased risk of glaucoma
This genotype indicates the presence of two copies of the Arg368His (R368H) variant, which is known to impair CYP1B1 enzyme function and is associated with primary congenital and juvenile glaucoma. Because this variant can affect ocular development, individuals with this genotype should consult with a medical professional or genetic counselor to discuss clinical monitoring and potential health implications.
This genotype is extremely rare in the general population.
Understanding rs104894468 and Its Genomic Context
The genetic variant known as rs104894468 is a specific alteration located within the CYP1B1 gene. In scientific literature, this variant is often identified by the amino acid substitution it causes, referred to as p.Arg368His, where the amino acid arginine is replaced by histidine at position 368 of the protein chain. This substitution occurs due to a change in the DNA sequence, which can alter the functional properties of the resulting protein. Because this variant is located in a critical gene responsible for normal eye development, it has been a subject of interest in ophthalmic genetics. It is categorized as a missense variant, meaning it changes the protein's instruction manual without completely deleting the gene's function. Understanding such variants requires looking at how they disrupt the fine-tuned biological processes necessary for maintaining healthy ocular structures from early development through adulthood.
The Role of CYP1B1 in Ocular Health
The CYP1B1 gene provides instructions for making an enzyme that belongs to the cytochrome P450 family. While these enzymes are famously involved in detoxifying substances in the liver, the CYP1B1 enzyme plays a specialized role in the eye. It is highly active in the tissues of the developing eye, specifically in the trabecular meshwork—the drainage system that regulates intraocular pressure. Research suggests that this enzyme is involved in the metabolism of endogenous compounds, such as retinoic acid and certain fatty acids, which are crucial signaling molecules for proper eye formation. When the CYP1B1 protein is misfolded or non-functional due to variants like rs104894468, it may fail to regulate these pathways effectively. This dysfunction can lead to developmental abnormalities in the eye's drainage channels, potentially resulting in elevated pressure within the eye, a hallmark of certain congenital and juvenile glaucoma conditions.
Associations and Evidence Strength
The scientific evidence linking rs104894468 to primary congenital glaucoma and juvenile open-angle glaucoma is significant but carries specific nuances. Clinical databases, including ClinVar, often classify this variant as pathogenic based on its recurrent observation in affected individuals and functional studies demonstrating reduced enzymatic activity. However, the strength of evidence regarding the predictive power of this variant for an individual remains limited in a general population context. While the variant is strongly associated with disease in families where the condition is hereditary, it is not a guaranteed diagnosis for everyone who carries it. The relationship between genotype and phenotype can be influenced by other genetic modifiers and environmental factors. Because it is a rare variant, large-scale population studies have less data to draw definitive conclusions about penetrance, or the proportion of people with the variant who actually develop symptoms.
What This Information Means for You
It is important to emphasize that identifying a genetic variant in your profile is not the same as receiving a medical diagnosis. Genetic variants in CYP1B1 are primarily investigated in the context of specific clinical symptoms related to eye development. If you or a family member have concerns about eye health, glaucoma, or vision changes, the most appropriate step is to consult an ophthalmologist or a board-certified genetic counselor. These professionals can interpret genetic data within the context of physical exams and family history. You cannot treat a genetic variant with lifestyle changes, but proactive monitoring of intraocular pressure by a specialist can be vital for those at higher risk. Always discuss any genetic findings with a qualified healthcare provider rather than attempting to manage potential health risks based on raw data reports.
How common is this variant?
Data from the Genome Aggregation Database (gnomAD) indicates that rs104894468 is an extremely rare variant, with a global minor allele frequency (MAF) of less than 0.0001. It has been observed globally across multiple ethnic groups.
Frequently asked questions
Is rs104894468 the only cause of congenital glaucoma?
No, congenital glaucoma is a complex condition that can be caused by many different genetic variants in CYP1B1 and several other genes. Genetic testing can help identify a specific cause, but many cases remain unexplained by current testing panels.
Should I be tested for this variant if I have a family history of glaucoma?
If there is a clear history of early-onset glaucoma in your family, genetic counseling and testing may be appropriate. A counselor can help determine if this specific variant is relevant to your family's situation.
Does carrying this variant mean I will definitely lose my vision?
Not necessarily. While this variant is associated with an increased risk for glaucoma, the severity and progression can vary widely between individuals. Regular check-ups with an eye doctor are the best way to monitor eye health and manage pressure.
Can diet or supplements fix a CYP1B1 mutation?
There is no evidence that diet or supplements can correct the underlying genetic function of the CYP1B1 gene. Current medical management focuses on monitoring and treating intraocular pressure to preserve vision.
Sources & further reading
Educational information only, last refreshed 9/17/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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This variant (p.Asn453Ser, formerly Val432Leu) in the CYP1B1 gene is associated with altered enzyme activity and has been investigated for susceptibility to various cancers, including breast and prostate cancer.
This variant (p.Gly61Glu) is a well-documented pathogenic mutation associated with primary congenital glaucoma (PCG) and is also studied for its role in oxidative stress and drug response pathways.
A missense variant in CYP1B1 (p.Ala119Ser) associated with primary congenital glaucoma and juvenile open-angle glaucoma risk.
A well-characterized loss-of-function missense variant causing primary congenital glaucoma through abnormal trabecular meshwork development.
Missense variant in CYP1B1 associated with primary congenital glaucoma.
A classic founder missense mutation in CYP1B1 responsible for early-onset recessive infantile and juvenile glaucoma.