Markers / Gene
MCM6
One position in this gene is readable from a home DNA test.
Digesting milk as an adult
rs4988235 · chr2:136,608,646 · G/A · evidence: established
Nearly every mammal switches lactase off after weaning. A single change upstream of the lactase gene keeps it on for life, and it spread through Europe in the last ten thousand years alongside dairying.
| If you carry | What it means |
|---|---|
| No copies | Likely lactase non-persistent |
| One copy | Likely lactase persistent |
| Two copies | Likely lactase persistent |
| Ancestry group | A (the effect version) | |
|---|---|---|
| African | 2.7% | |
| American | 21.6% | |
| East Asian | 0.0% | |
| European | 50.8% | |
| South Asian | 11.3% |
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