rs16991615

A SNP in the MCM8 gene on chromosome 20. Its most notable genotype is A;A: age at menopause increased by avg of 22 months

Gene
MCM8
Location
Chr 205,967,581 (GRCh38)
Highest magnitude
1.5Minor
Tested on
23andMe, AncestryDNA
Minor allele frequency
3%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. A;AMost notableNot ratedage at menopause increased by avg of 22 monthsMinor · 1.5<1% of people
  2. A;GGoodslight increase (11 months) in avg age at menopauseMinor · 1.56% of people
  3. G;GGoodcommon on affy axiom dataTypical · 0.094% of people

On SNPedia: (A;A), (A;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Frequency

Share of each genotype in 7 HapMap populations.

  • AverageA;A <1% A;G 6% G;G 94%
  • European ancestry (Utah)A;A <1% A;G 17% G;G 82%
  • Han Chinese (Beijing)A;A 0% A;G 0% G;G 100%
  • Japanese (Tokyo)A;A 0% A;G 0% G;G 100%
  • Yoruba (Nigeria)A;A 0% A;G 0% G;G 100%
  • Gujarati IndianA;A 0% A;G 4% G;G 96%
  • Mexican ancestry (Los Angeles)A;A 0% A;G 10% G;G 90%
  • TuscanA;A 2% A;G 10% G;G 88%

Notes

From SNPedia

Show notes, about 120 words

rs16991615 is a nonsynonymous SNP on chromosome 20. A case control study of ~2,000 women found that each rs16991615(A) allele was associated with an average increase in age at menopause of 11 months. This also meant that each rs16991615(G) allele yielded an odds ratio of 1.85 (CI: 1.51&#8211;2.2, p = 1.45 x 10e-9) of early menopause, defined as occurring before the age of 46. Overall, women homozygous for the "early" alleles at all 4 SNPs found in this study were ~4 times more likely to undergo menopause early compared to women who had a total of 3 or less risk alleles. However, the ability to predict which women will actually undergo early menopause using these 4 SNPs is still low. * see also 23andMe blog

Source and license

Adapted from rs16991615 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.

SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.