HMCES rs117737301: What Your Genotype Means
The rs117737301 variant is a genetic marker located in the upstream region of the HMCES gene. Research has associated this variant with variations in the age at which women reach natural menopause and the regulation of ovarian reserve longevity.
What each genotype means
Typical menopause timing profile
You carry two copies of the common C allele at this upstream HMCES site. Large-scale association studies have not linked this baseline genotype with altered ovarian reserve longevity or significant shifts in natural menopause timing. Your baseline genetic contribution from this specific locus aligns with typical population averages.
Carried by approximately 80% to 90% of individuals of East Asian ancestry and the vast majority (>99%) of individuals of European ancestry.
Modestly altered menopause timing
You carry one copy of the less common T allele near the HMCES gene. In genome-wide association studies, this allele has shown a limited statistical association with modest variation in the age at natural menopause and markers of ovarian reserve. Because evidence is limited and reproductive timing is influenced by many combined genetic and lifestyle factors, having one copy does not indicate premature ovarian insufficiency or guarantee a noticeable shift in menopause onset.
Found in approximately 10% to 18% of individuals of East Asian ancestry, but rare (<1%) in European and African populations.
Altered reproductive timing profile
You carry two copies of the minor T allele near the HMCES locus. Research associating this variant with differences in natural menopause age suggests homozygous carriers may experience a modest shift in ovarian reserve longevity compared to the baseline genotype. However, because published evidence remains limited and reproductive lifespan is multifactorial, this genotype alone does not diagnose any reproductive disorder or reliably predict your exact age at menopause.
Present in roughly 0.5% to 1% of East Asian populations and exceedingly rare in other ancestral groups.
Understanding the Variant
The rs117737301 variant is a single nucleotide polymorphism (SNP) situated in the upstream regulatory region of the HMCES gene. In genomics, an upstream variant is located in the DNA sequence preceding the gene's coding region, where it may influence how, when, or how much of a protein is produced. While this variant does not change the protein structure itself, its location suggests a potential role in gene expression regulation. Scientists identify such variants through genome-wide association studies (GWAS), which scan the entire genome to find statistical correlations between specific DNA changes and observable traits. Because rs117737301 is located in a non-coding region, its functional impact is likely mediated through complex interactions with cellular machinery that controls gene activity rather than by altering the HMCES protein directly.
The Role of the HMCES Gene
The HMCES gene provides instructions for creating a protein that plays a critical role in maintaining genomic stability. Specifically, the HMCES protein acts as a DNA cross-linking enzyme that senses abasic sites—areas where a DNA base is missing—within single-stranded DNA at replication forks. By identifying these sites, the protein helps protect the genome from damage during the process of cell division. In the context of reproductive health, HMCES has been identified as an embryonic stem cell-specific binding protein for 5-hydroxymethylcytosine, an epigenetic modification that is dynamically regulated during the aging of oocytes. Because the quality and quantity of the ovarian reserve are highly dependent on the integrity of DNA within oocytes, the function of HMCES is considered a relevant biological factor in the timing of reproductive aging.
Research and Evidence Strength
The association between rs117737301 and the age at natural menopause is supported by large-scale genetic studies, including meta-analyses that integrate data from diverse populations. Research has identified HMCES as a candidate gene in the regulation of menopause timing, with some studies highlighting its correlation with other reproductive traits. However, the evidence strength for this specific variant is currently categorized as limited. While statistical associations have been observed, the biological mechanisms linking this specific upstream variant to the clinical timing of menopause are still being investigated. Furthermore, genetic associations with complex traits like menopause are often influenced by multiple genes and environmental factors. Consequently, while rs117737301 is a recognized marker in the literature, it should be viewed as one piece of a much larger, complex genetic puzzle rather than a definitive predictor of reproductive outcomes.
Population Frequency
The frequency of the rs117737301 variant varies significantly across different ancestral groups. It is observed at a low-to-moderate frequency in East Asian populations, typically ranging between 0.05 and 0.10. In contrast, the variant is considered rare in European populations. This disparity highlights the importance of trans-ethnic research in genomics; findings identified in one population may not always be replicated or hold the same statistical weight in another due to differences in genetic architecture, evolutionary history, and environmental factors. Researchers emphasize that these differences in allele frequency are common and underscore the need for diverse study cohorts to fully understand the global landscape of genetic associations with reproductive health.
Interpreting Your Information
Information regarding genetic variants like rs117737301 is intended for educational purposes and should not be used for medical diagnosis or personal health decision-making. Because the timing of menopause is a complex trait influenced by a combination of genetics, lifestyle, and environmental factors, a single SNP cannot predict an individual's reproductive timeline. If you have concerns about your reproductive health, fertility, or the timing of menopause, it is essential to consult with a qualified healthcare provider or a reproductive endocrinologist. They can provide personalized guidance based on your clinical history and current health status. Genetic data provides a window into biological predispositions, but it does not replace professional medical evaluation or clinical testing.
How common is this variant?
The rs117737301 variant shows low-to-moderate frequency in East Asian populations (~0.05-0.10) and is rare in European populations.
Frequently asked questions
Can this variant predict when I will reach menopause?
No, this variant cannot predict the timing of menopause. Menopause is a complex trait influenced by many genetic and environmental factors, and this SNP only provides a small statistical association.
Is HMCES related to fertility?
HMCES is involved in DNA repair processes that are important for maintaining the integrity of oocytes. While it is linked to reproductive aging, it is not a direct measure of individual fertility.
Why is the frequency of this variant different between populations?
Differences in allele frequencies are common due to evolutionary factors like genetic drift, natural selection, and migration. These variations are why genetic studies must include diverse populations to be accurate.
Should I be concerned if I have the G allele?
No, there is no reason for concern. This variant is a normal part of human genetic diversity and is not considered a disease-causing mutation.
Sources & further reading
Educational information only, last refreshed 10/18/2026. Not medical advice — these associations describe population statistics, not individual predictions.
Curious what your genotype is for rs117737301?
Upload a raw DNA file from 23andMe, AncestryDNA, MyHeritage, or FamilyTreeDNA and see this variant — plus thousands more — interpreted in your full report.
Get my report — $29