rs1695
One of the enzymes that mops up reactive chemicals
What this position does
Glutathione S-transferases attach a handle to reactive molecules so the body can throw them out. They handle smoke, cooked food, industrial solvents and the by-products of your own metabolism. This is the most studied position in the family.
Liver. Shaped by smoke, plants and industrial chemicals. This is one of the variants that differs sharply between human populations, because something in the environment made one version worth having.
A chemical environment that keeps changing
The liver evolved to clear what plants and smoke put into people. It now also handles drugs, solvents and the products of charred meat, which arrived far too recently to have shaped anything.
What changed: Industry, roughly the last two centuries. Indoor work, heated buildings, refined food, cheap salt and sugar, tobacco at scale, and a collapse in infectious disease. This is where most of the deals in your genome came undone.
Why it spread: nobody knows. The frequency difference between populations is real and measured. What the variant was worth having for is not known, and any site that tells you is guessing.
Spiral Staircase, chapter 14: The Liver and the Chemical Century Spiral Staircase is written by the same author as this site.
What each result means
| If you carry | What it means |
|---|---|
| No copies of the effect version AA | You have the standard version on both copies The more common form of the enzyme. |
| One copy AG | You carry one variant copy Altered enzyme activity, higher for some substrates and lower for others. |
| Two copies GG | You have the variant version on both copies Different activity again. Which direction counts as better depends entirely on what you are exposed to, which is why claims that one version is healthier should be treated carefully. |
Worth knowing. Popular detox testing leans heavily on this gene family and greatly overstates what a single position means.
How common each version is
| Ancestry group | G (the effect version) | |
|---|---|---|
| African | 48.0% | |
| American | 47.6% | |
| East Asian | 17.9% | |
| European | 33.1% | |
| South Asian | 29.4% |
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.
How many people carry each result
| Ancestry group | AA | AG | GG |
|---|---|---|---|
| African | 175 / 661 | 337 / 661 | 149 / 661 |
| European | 224 / 503 | 225 / 503 | 54 / 503 |
| East Asian | 339 / 504 | 150 / 504 | 15 / 504 |
| South Asian | 251 / 489 | 188 / 489 | 50 / 489 |
| American | 98 / 347 | 168 / 347 | 81 / 347 |
Counts of people, not modelled frequencies: every one of the 2,504 individuals sequenced by the 1000 Genomes Project phase 3, tallied by the genotype they carry. Deriving these from allele frequencies instead would assume random mating inside each group and undercount the homozygotes.
How to find out which you have
If you have taken a test with 23andMe, AncestryDNA, MyHeritage, Family Tree DNA, TellMeGen or Living DNA, this position is very likely already in the raw data file they gave you. You do not need another test.
One thing to watch if you look it up by hand: testing companies report some positions from one DNA strand and some from the other, and the file does not say which. Read the letters as they appear and you will get the opposite of the truth for some positions. Sequencings resolves that automatically.
Source
Coordinates and allele pair verified against Ensembl GRCh37. Direction of effect verified against VEP protein consequences or 1000 Genomes population frequency. Category: Population adaptation.
Common questions
What is rs1695?
rs1695 is a position in the GSTP1 gene on chromosome 11. Glutathione S-transferases attach a handle to reactive molecules so the body can throw them out. They handle smoke, cooked food, industrial solvents and the by-products of your own metabolism. This is the most studied position in the family.
What does it mean if I have GG at rs1695?
You have the variant version on both copies. Different activity again. Which direction counts as better depends entirely on what you are exposed to, which is why claims that one version is healthier should be treated carefully.
What does it mean if I have AA at rs1695?
You have the standard version on both copies. The more common form of the enzyme.
How do I find out my rs1695 genotype?
If you have taken a home DNA test, this position is very likely in the raw data file you were given. Sequencings reads that file in your browser without uploading it, and resolves which DNA strand each position was reported from, which is the step most manual lookups get wrong.
This is reference information, not medical advice, and not a diagnosis. See the medical disclaimer. Category: Population adaptation.