Kathleen Klosterman 

     I'm not sure that one can judge the accuracy of bio-age measurements done with DNA methylation simply by how many site-methylations are measured.  All cells have the same DNA, but they become specialized to become nerve cells or liver cells or heart cells based on how their epigenome is structured, in part by DNA methylation that plays a role in "silencing" unwanted genes.   Therefore, every cell type will have a characteristically different DNA methylation pattern.

    What Prof. Steve Horvath of UCLA did, using his command of statistics and AI techniques, was to identify that small subset of the measured DNA methylation sites that (a) are common to all or most cell types, and (b) have a significant correlation (positive or negative) with calendar age.  He found that 353 methylation sites (out of a much larger number) fulfill these criteria.  Most of the DNA methylation has nothing to do with aging.

     If you try to increase test accuracy by including more sites, you may be just adding the "noise" of cell-type-dependent methylation to the mix and doing more harm than good.  Therefore, just because your test "measures over 100,000 areas", that does not mean that it is necessarily a better test.

JGC The person who developed my test is Dr. Levine who studied and worked with Dr. Hovarth at UCLA for many years. She has since moved on to Yale and is a chief science officer at Elysium. So, I believe her test best, an improvement over Hovarth's original blood test. But, thanks for your clarification.

Kathleen Klosterman Confused, I don't understand what your reason is why you think her test is best? Unless you are saying you think her test is best because she works for Yale and Elysium?

Kathleen Klosterman Guarente is (still?) Elysium's SCO, not Levine.

JGC Yeah, I wonder if more the methylation sites the better? Bioviva just released a new test on a new testing platform that tests over 850,000 sites. Does that make it more accurate? Who knows.

https://bioviva-science.com/products/timekeeper%E2%84%A2-dna-methylation-kit?variant=31445016248368

JGC Isn't myDNAge the consumer/retail version of the Zymo test? I.e. Aren't they (supposed to be) identical?

aribadabar 

    Zymo and myDNAge do have the same cost, and both offer blood and urine versions.  Also, I believe myDNAge was started by a former Zymo person.  However, It isn't clear that they are identical or why one would be more "consumer/retail" than the other.  The myDNAge website says:

    "The myDNAge® Epigenetic Aging Clock service is based on Steve Horvath’s aging clock and utilizes SWARM™ (Simplified Whole-panel Amplification Reaction Method) technology to analyze DNA methylation patterns of >2000 genetic loci and provide epigenetic age predictions in a high throughput manner."

    I don't think Horvath ever used >2,000 CpG sites.

JGC Is there a consumer-oriented DNA methylation service  currently offered by Zymo?

The way their website is structured points to submitting an enquiry presumably by a person affiliated with a certain institution and not a retail offering. That's why I described it as such in the previous post.

Right, Horvath does not have a 2000-loci-based clock. MyDNAge formula is "proprietary" and "based" (read: inspired) by Horvath and nothing else. Horvath's clock is using 353 CpG sites so clearly myDNAge are offering something totally different.

aribadabar 

    I've had two Zymo tests (one still in progress), but both were arranged for me by Johnny Adams.  I'm under the impression that you can set up a Zymo test by making an inquiry, but I've never done it.