rs13387042

A SNP in the LOC105373874 gene on chromosome 2. Its most notable genotype is A;A: 1.24x increased risk for breast cancer

Gene
LOC105373874
Location
Chr 2217,041,109 (GRCh38)
Highest magnitude
1.3Minor
Tested on
23andMe, AncestryDNA
Minor allele frequency
45%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. A;AMost notableBad1.24x increased risk for breast cancerMinor · 1.331% of people
  2. A;GBad1.12x increased risk for breast cancerMinor · 1.136% of people
  3. G;GNot ratednormalTypical · 0.034% 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 11 HapMap populations.

  • AverageA;A 31% A;G 36% G;G 34%
  • European ancestry (Utah)A;A 32% A;G 49% G;G 20%
  • Han Chinese (Beijing)A;A 2% A;G 19% G;G 79%
  • Japanese (Tokyo)A;A 2% A;G 17% G;G 81%
  • Yoruba (Nigeria)A;A 60% A;G 36% G;G 4%
  • African ancestry (Southwest US)A;A 51% A;G 47% G;G 2%
  • Chinese (Denver)A;A 0% A;G 28% G;G 73%
  • Gujarati IndianA;A 32% A;G 45% G;G 24%
  • Luhya (Kenya)A;A 66% A;G 32% G;G 3%
  • Mexican ancestry (Los Angeles)A;A 17% A;G 38% G;G 45%
  • Maasai (Kenya)A;A 54% A;G 39% G;G 7%
  • TuscanA;A 23% A;G 44% G;G 33%

Conditions, medicines and genes

Notes

From SNPedia

Notes

rs13387042(A;A) has an estimated 1.44-fold greater risk of breast cancer than the GG genotype. This initial association was later tested among patients in the Breast Cancer Association Consortium, including 31,510 women with invasive breast cancer, 1101 women with ductal carcinoma in situ (DCIS), and 35,969 controls. In Caucasian women of European origin, each A allele is associated with 1.12 higher odds (CI: 1.09-1.15). This association held regardless of ER or PR status.

Source and license

Adapted from rs13387042 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.