Markers / Gene
ADA
One position in this gene is readable from a home DNA test.
How deeply you sleep
rs73598374 · chr20:43,280,227 · C/T · evidence: moderate
Adenosine is the molecule that builds up while you are awake and makes you feel sleepy, and it is what caffeine blocks. This variant slows the enzyme that breaks adenosine down, so sleep pressure builds higher, and carriers show measurably more deep slow-wave sleep.
| If you carry | What it means |
|---|---|
| No copies | You have the faster enzyme on both copies |
| One copy | You carry one slower copy |
| Two copies | You have the slower enzyme on both copies |
| Ancestry group | T (the effect version) | |
|---|---|---|
| African | 0.2% | |
| American | 2.0% | |
| East Asian | 6.3% | |
| European | 6.2% | |
| South Asian | 11.7% |
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