rs3842787

A SNP in the PTGS1 gene on chromosome 9. Its most notable genotype is T;T: Higher risk of bleeding during coronary angiography

Gene
PTGS1
Location
Chr 9122,371,228 (GRCh38)
Highest magnitude
3.0Important
Tested on
23andMe, AncestryDNA, FamilyTreeDNA
Minor allele frequency
7%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CGoodnormalTypical · 0.080% of people
  2. C;TBadHigher risk of bleeding during coronary angiographyWorth knowing · 2.019% of people
  3. T;TMost notableBadHigher risk of bleeding during coronary angiographyImportant · 3.01% 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 8 HapMap populations.

  • AverageC;C 80% C;T 19% T;T 1%
  • European ancestry (Utah)C;C 84% C;T 16% T;T 0%
  • Yoruba (Nigeria)C;C 68% C;T 31% T;T 1%
  • African ancestry (Southwest US)C;C 63% C;T 34% T;T 4%
  • Gujarati IndianC;C 97% C;T 3% T;T 0%
  • Luhya (Kenya)C;C 72% C;T 27% T;T 2%
  • Mexican ancestry (Los Angeles)C;C 91% C;T 9% T;T 0%
  • Maasai (Kenya)C;C 72% C;T 27% T;T 1%
  • TuscanC;C 96% C;T 4% T;T 0%

Conditions, medicines and genes

Other PTGS1 SNPs

All PTGS1 SNPs

Notes

From SNPedia

Show notes, about 130 words

rs3842787, also known as 50C>T, is a SNP in the signal peptide region of the cyclooxygenase-1 PTGS1 gene. A study of 696 European patients undergoing elective diagnostic coronary angiographies (CAGs) because of suspected or proven stable coronary artery disease found that 23 experienced bleeding, perhaps the most common complication of this type of invasive coronary procedure. After controlling for various variables (especially gender), two co-inherited SNPs, rs10306114 and rs3842787, were found to be associated with higher risk for bleeding in otherwise low risk patients who (i) did undergo percutaneous coronary intervention and (ii) did not take clopidogrel. Having the less common haplotype (rs10306114(G) and/or rs3842787(T)) increases the bleeding risk upon CAG ~12 fold (p = 0.012).

Source and license

Adapted from rs3842787 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.