Markers / Gene
F2
One position in this gene is readable from a home DNA test.
Prothrombin G20210A
rs1799963 · chr11:46,761,055 · G/A · evidence: established
A change in the prothrombin gene that raises circulating prothrombin and, with it, clotting tendency. The second most common inherited clotting variant after Factor V Leiden.
| If you carry | What it means |
|---|---|
| No copies | You do not carry this variant |
| One copy | You carry one copy, so clotting risk is modestly raised in specific situations |
| Two copies | You carry two copies, worth raising with a doctor |
| Ancestry group | A (the effect version) | |
|---|---|---|
| African | 0.0% | |
| American | 1.4% | |
| East Asian | 0.0% | |
| European | 0.8% | |
| South Asian | 0.0% |
1000 Genomes Project phase 3, via Ensembl, retrieved 2026-09-23. These groupings are coarse and flatten a great deal of internal diversity, particularly within Africa. A variant being common somewhere tells you where a piece of your ancestry probably comes from, and nothing else.
Where this gene fits
If you have taken a home DNA test, these positions are already in your file.
Read my file