Epi-Testosterone is one of several naturally-occurring testosterone compounds in the body that act as steroids.
Some male and females have an issue getting testosterone into the form in which it's excreted in urine. In the blood testosterone gets turned into testosterone-glucuronide (a water-soluble phase 2 conjugate) and then it ends up in urine. This is a good way to measure testosterone in urine. However, there is an enzyme that is responsible for moving it from testosterone to testosterone-glucuronide. In a small fraction of the population (more common in asian populations) there is a defective form of this enzyme where, although not harmful, urine testing becomes a false low for testosterone. This enzyme is called UGT enzyme. This means that your urine level testosterone can show up artifically low, although your serum level testosterone is normal.
Testosterone and Epi-Testosterone are usually in similar concentrations. Testosterone is conjugated by this UGT enzyme and Epi-Testosterone is conjugated by a different enzyme.
So this biomarker becomes helpful to look at if the ratio of those 2 markers is out of balance, hence the urine testosterone levels are reported artificially low.
- UGT not only conjugates testosterone, but also the metabolites 5a-DHT and 5b-Androstanediol.
- 5a-Androstanediol and Epi-Testosterone are not conjugated by UGT.
So if you look at your DUTCH test results and see that these three results are low:
- Testosterone is low,
- 5a-DHT is low
- 5b-Androstanediol is low
...but 5a-Androstanediol and Epi-Testosterone are not low, you might have the defect UGT enzyme which would explain why your urine testosterone levels are low. In order to fully confirm the situation, it is recommended to measure your blood testosterone levels (‘free’ and ‘total’ testosterone should be measured).
If your testosterone levels and Epi-testosterone levels are in a similar range then you can rest assured that your urine testosterone levels are accurate.
Epi-Testosterone (male)
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