rs4986761

A SNP in the ATM gene on chromosome 11. Its most notable genotype is C;C: very slightly increased (1.5x or less) breast cancer risk

Gene
ATM
Location
Chr 11108,254,034 (GRCh38)
Highest magnitude
1.5Minor
Tested on
23andMe, AncestryDNA, FamilyTreeDNA
Minor allele frequency
<1%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CMost notableBadvery slightly increased (1.5x or less) breast cancer riskMinor · 1.50% of people
  2. C;TBadvery slightly increased risk (1.05) for breast cancerMinor · 1.01% of people
  3. T;TGoodnormalTypical · 0.099% of people

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

Frequency

Share of each genotype in 5 HapMap populations.

  • AverageC;C 0% C;T 1% T;T 99%
  • European ancestry (Utah)C;C 0% C;T <1% T;T 99%
  • Han Chinese (Beijing)C;C 0% C;T 2% T;T 99%
  • Japanese (Tokyo)C;C 0% C;T 0% T;T 100%
  • Yoruba (Nigeria)C;C 0% C;T 0% T;T 100%
  • TuscanC;C 0% C;T 4% T;T 96%

Conditions, medicines and genes

Other ATM SNPs

All ATM SNPs

Notes

From SNPedia

Show notes, about 120 words

This SNP, also known as S707P, a variant in the ATM gene, is 1 of 25 SNPs reported to represent independently minor, but cumulatively significant, increased risk for breast cancer. For details of all 25 SNPs in this group, along with the two methods used to calculate overall risk estimates for breast cancer, refer to the SNPedia breast cancer entry. For this particular SNP, the risk (minor) allele is (C). Another large meta-analysis published in 2011, comprising 26,000+ breast cancer cases and almost 30,000 controls from 23 studies in the Breast Cancer Association Consortium, found average odds ratios of 1.05 for heterozygotes and 1.51 for homozygotes of each of 5 ATM gene SNPs, of which this is one.

Source and license

Adapted from rs4986761 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.