CRYAA rs104894334: Understanding This Genetic Variant
The rs104894334 variant is a specific genetic change located within the CRYAA gene. It is associated with the structural integrity of lens proteins and has been linked in research to cases of autosomal dominant congenital cataracts.
What each genotype means
Typical lens protein structure
This genotype represents the common, expected sequence for the CRYAA gene in the general population. It is associated with the normal production of alpha-crystallin, a protein essential for maintaining lens transparency. There is no evidence suggesting this genotype contributes to the development of congenital cataracts.
This is the most common genotype found in the vast majority of the global population.
Potential cataract risk variant
This genotype indicates the presence of a rare missense mutation in the CRYAA gene, which may alter the structural chaperone function of lens alpha-crystallin. Research associates such variants with an increased risk of developing autosomal dominant zonular cataracts. Because this is a rare finding, you should discuss any concerns regarding vision or eye health with an ophthalmologist or genetic counselor.
This genotype is extremely rare, with an allele frequency reported at less than 0.00001 in large-scale population databases like gnomAD.
Rare variant homozygous state
This genotype indicates that both copies of the CRYAA gene carry this specific rare mutation. Mutations in this gene are known to disrupt lens protein stability and are linked to congenital cataract conditions. Given the rarity of this variant, its clinical implications are not fully characterized in the general population, and professional clinical evaluation is recommended for any related symptoms.
This genotype is exceptionally rare and is not typically observed in standard population frequency datasets.
What is the rs104894334 Variant?
The rs104894334 variant is a single nucleotide polymorphism (SNP) located within the CRYAA gene. In genetics, a SNP represents a variation at a single position in the DNA sequence among individuals. This specific variant is categorized as a missense mutation, meaning the change in the DNA sequence results in a different amino acid being incorporated into the protein chain. Because the CRYAA gene provides instructions for creating a protein essential for the clarity of the eye's lens, alterations in this sequence can potentially impact how that protein functions. Researchers study such variants to understand how they might disrupt normal biological processes, particularly those related to the development and maintenance of eye structures.
The Role of the CRYAA Gene
The CRYAA gene encodes the alpha-A crystallin protein, which is a member of the small heat shock protein family. This protein acts as a molecular chaperone, a specialized molecule that helps other proteins fold correctly and prevents them from clumping together, or aggregating. In the human eye, alpha-A crystallin is highly concentrated in the lens, where it is vital for maintaining transparency. By ensuring that other lens proteins remain soluble and properly structured, it protects the lens from becoming cloudy. Because the lens is a highly specialized tissue that must remain clear to focus light, the chaperone activity of CRYAA is critical. When this gene is disrupted, the resulting protein may lose its ability to prevent aggregation, which can lead to the formation of opacities known as cataracts.
Research and Clinical Associations
Scientific research has associated certain mutations in the CRYAA gene with autosomal dominant congenital cataracts. These are conditions where clouding of the lens is present at or shortly after birth and follows a dominant inheritance pattern. Studies have investigated how missense mutations in this gene can alter the structural chaperone function of the alpha-A crystallin protein, often leading to protein instability or the formation of precipitates within lens cells. While the evidence linking specific CRYAA variants to these conditions is documented in clinical literature, the strength of the association can vary depending on the specific mutation. It is important to note that the presence of a variant does not guarantee a clinical diagnosis, and research in this field is ongoing to better understand the spectrum of phenotypes associated with different CRYAA alterations.
Population Frequency
According to large-scale genomic databases like gnomAD, the rs104894334 variant is extremely rare, with an allele frequency reported at less than 0.00001. This low frequency indicates that the variant is not commonly found in the general population. Because it is so rare, it is primarily identified in the context of clinical studies focusing on individuals or families with specific inherited eye conditions. The rarity of this variant underscores that it is not a common feature of human genetic diversity but rather a specific change that has been observed in limited clinical settings.
Understanding Your Genetic Information
Genetic information regarding variants like rs104894334 should be interpreted with caution and in consultation with qualified healthcare professionals. While research identifies associations between specific genetic changes and health traits, these findings are often based on clinical cohorts and may not apply to every individual. If you have concerns about your vision or a family history of eye conditions, it is best to speak with an ophthalmologist or a genetic counselor. They can provide context based on your personal health history and clinical presentation. This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a physician or other qualified health provider with any questions regarding a medical condition.
How common is this variant?
The rs104894334 variant is extremely rare, with a gnomAD allele frequency of less than 0.00001 across global populations.
Frequently asked questions
What is a congenital cataract?
A congenital cataract is a clouding of the lens of the eye that is present at birth or develops during early childhood. It can affect one or both eyes and may vary in severity, potentially impacting vision development.
Does having a CRYAA variant mean I will have cataracts?
Not necessarily. While certain variants in the CRYAA gene are associated with an increased risk of congenital cataracts, genetic factors are complex. A clinical diagnosis requires an evaluation by an eye care professional.
How are genetic eye conditions diagnosed?
Diagnosis typically involves a comprehensive eye examination by an ophthalmologist. In some cases, genetic testing may be recommended to identify specific variants that could explain the underlying cause of the condition.
Can I change my genotype?
No, your genotype is determined at conception and remains the same throughout your life. Genetic information provides insight into your biological makeup but cannot be altered by lifestyle or environmental changes.
Sources & further reading
Educational information only, last refreshed 9/22/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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Promoter variant in CRYAA associated with age-related cataracts.
A pathogenic missense mutation in alpha-A crystallin causing autosomal dominant congenital and pediatric cataracts.
A pathogenic missense mutation in the alpha-A crystallin gene causing autosomal dominant congenital cataracts.
This variant in the alpha A-crystallin gene has been studied for its potential association with susceptibility to nuclear age-related cataracts in Han Chinese populations.