BRCA1 rs4986852: Understanding This Genetic Variant
The rs4986852 variant is a single nucleotide polymorphism located within the BRCA1 gene. It results in an amino acid substitution known as Ser1040Asn and has been studied for its potential role in breast cancer susceptibility.
What each genotype means
Common genetic profile
This genotype represents the most common version of this BRCA1 variant, where both copies of the gene encode the amino acid serine at position 1040. Research generally considers this the normal or reference state for this specific location in the BRCA1 protein.
This is the most frequent genotype observed across global populations.
Possible predisposition variant
This genotype means you carry one copy of the rare A allele, which results in an amino acid change from serine to asparagine (Ser1040Asn). While this variant has been investigated for potential links to breast cancer predisposition, the clinical significance remains a subject of ongoing research and is often classified as a variant of uncertain significance.
Carried by a small percentage of the population, consistent with a global minor allele frequency of approximately 1.2%.
Rare variant carrier
This genotype indicates that both copies of your BRCA1 gene carry the rare A allele, resulting in the Ser1040Asn change on both proteins. Scientific literature has explored this variant in the context of breast cancer susceptibility, but evidence is limited and mixed regarding its specific impact on individual risk.
This is a rare genotype, occurring significantly less frequently than the heterozygous state in most populations.
What is rs4986852?
The variant rs4986852 is a specific change in the DNA sequence of the BRCA1 gene, which is located on the long arm of chromosome 17. In genetics, a single nucleotide polymorphism (SNP) like this represents a variation at a single position in the DNA building blocks. This particular variant causes a missense mutation, meaning it leads to the replacement of one amino acid with another in the resulting protein—specifically, the amino acid serine is replaced by asparagine at position 1040. Because the BRCA1 gene is critical for maintaining genomic stability, researchers often investigate how such structural changes might influence the protein's function. This variant is cataloged in major genomic databases, allowing scientists to track its presence across different human populations and study its potential biological impact.
The Role of the BRCA1 Gene
The BRCA1 gene provides instructions for making a protein that acts as a tumor suppressor. Tumor suppressor proteins help prevent cells from growing and dividing too rapidly or in an uncontrolled way. The BRCA1 protein is primarily involved in repairing damaged DNA, which is essential for maintaining the integrity of a cell's genetic material. When DNA damage occurs, BRCA1 helps coordinate the repair process, ensuring that cells do not accumulate mutations that could lead to cancer. Because of its vital role in DNA repair, inherited mutations in BRCA1 are well-known for significantly increasing the risk of developing certain cancers, particularly breast and ovarian cancer. Understanding how variants like rs4986852 affect this protein is a major focus of ongoing cancer research.
Research and Evidence Strength
The association between rs4986852 and cancer risk is considered to have moderate evidence. While the BRCA1 gene is strongly linked to hereditary cancer syndromes, not every variant within the gene carries the same clinical significance. Many missense variants are classified as variants of unknown clinical significance (VUS) until further functional studies or large-scale epidemiological data can confirm their impact. Research into rs4986852 has explored whether this specific amino acid change alters the protein's ability to suppress tumors, but results have been mixed or inconclusive regarding its contribution to cancer risk in the general population. It is important to distinguish between high-penetrance mutations that cause clear disease syndromes and common polymorphisms that may have only subtle or no measurable effects on health.
Interpreting Your Information
If you have information about your genotype for rs4986852, it is important to understand that this data does not constitute a medical diagnosis. Genetic variants are only one piece of a complex puzzle that includes family history, lifestyle factors, and other genetic influences. Because the evidence for this specific variant is not definitive, it should not be used to make clinical decisions about cancer screening or prevention. If you are concerned about your personal or family history of cancer, the most appropriate step is to consult with a certified genetic counselor or a healthcare provider. They can help you interpret your genetic information in the context of your overall health and guide you toward evidence-based screening recommendations that are appropriate for your specific situation.
How common is this variant?
The global minor allele frequency (GMAF) for rs4986852 is approximately 0.01194, indicating that the variant is relatively uncommon across most studied populations.
Frequently asked questions
Is rs4986852 a cause of breast cancer?
The rs4986852 variant is a common polymorphism in the BRCA1 gene, but it is not classified as a high-risk mutation that directly causes hereditary breast cancer. Current research has not established a definitive link between this specific variant and a significant increase in cancer risk.
Should I get tested for this variant?
Routine testing for this specific variant is not typically recommended for the general population. Genetic testing for BRCA1 is usually reserved for individuals with a strong personal or family history of breast or ovarian cancer, as determined by a healthcare professional.
What does 'Ser1040Asn' mean?
This notation describes the specific change in the BRCA1 protein. It means that at position 1040 of the protein chain, the amino acid serine (Ser) has been replaced by asparagine (Asn).
Can I change my risk if I have this variant?
Because the impact of this variant is not clearly established, there are no specific lifestyle changes or medical interventions linked to it. Maintaining a healthy lifestyle and following standard cancer screening guidelines are the best ways to manage general health.
Sources & further reading
Educational information only, last refreshed 9/26/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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This variant is a known pathogenic mutation in the BRCA1 gene, which significantly increases the lifetime risk of developing breast and ovarian cancer.
This variant in the BRCA1 gene is associated with a minor but cumulatively significant increase in breast cancer risk.
This rare variant has been recently annotated in clinical databases as a potential contributor to hereditary breast and ovarian cancer risk.
This variant is one of 25 SNPs identified as contributing to a cumulative, albeit minor, increased risk for breast cancer.
This variant in the BRCA1 gene is clinically classified as pathogenic and is associated with an increased risk for breast cancer.
This variant is a pathogenic BRCA1 mutation associated with an increased risk of hereditary breast and ovarian cancer.