I’ve been pondering the accuracy of currently available epigenetic age tests. I believe the following protocol would be best used to create new and more accurate epigenetic age tests that can truly show an increase in lifespan.
I think the best way to develop an epigenetic age test is to see how well it performs amongst the following 4 cohorts - a control group of mice, a Rapamycin-treated group of mice that had proven extended lifespan, a control group of marmosets, and a Rapamycin-treated group of marmosets that had proven extended lifespan. Then, determine which epigenetic changes are most important between the groups to determine what the epigenetic tests should look for. Since the two Rapamycin-treated groups have proven extended lifespan, it should lead to clues as to which epigenetic factors are most important for lifespan extension.
Steve Horvath, the founding father of epigenetic age tests, did test the Rapamycin-treated marmosets using the currently available epigenetic age tests and found that there was no difference in epigenetic age results between the two groups of marmosets. This tells us that the current set of epigenetic age tests are testing the wrong biomarkers if we want to measure the effectiveness of lifespan extending treatments such as Rapamycin!