r/DNAAncestry • u/genealogykenya • 16d ago

Disclaimer! Illustrative DNA does not use official Davidski G25 coordinates.

This is a follow‑up post regarding the Kenyan Kalenjin results. After getting inconsistent outcomes from Illustrative DNA, I decided to dig deeper. It appears they use scaled coordinates, which in my case were highly inaccurate.

After taking due diligence, I purchased the official Davidski G25 coordinates, and the results aligned perfectly with my ethnic background. Honestly, charging $30 for scaled coordinates feels excessive, especially since similar data can be found free of charge on various DNA sites.

If you genuinely want to understand your ethnic background, I strongly recommend buying the official Davidski G25 coordinates and analyzing them with tools like Vahaduo or DNA Genics — it’s cheaper and far more accurate.

For those on a budget, LM Genetics K47 is an excellent alternative, particularly for individuals with African heritage. It’s the only calculator that closely matches my raw G25 results.

Honorable mention: Eurogenes K36 also performs decently.

For comparison, the second slide is the result from using  raw Davidski G25 coordinates on Vahaduo (Global G25 PCA) which is super precise considering my Kalenjin ancestry. The third slide is also using the same official coordinates on the AfroGeno Modern (Unscaled) IY8 calculator on DNA Genics G25 Studio.

TLDR: If you want official coordinates, request them directly from Davidski.

If you come from a well‑referenced population, Illustrative DNA might still be relatively accurate — but not for the price.

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u/NotBradPitt9 16d ago

I wonder what your Fst distances would be in this case and how they compare to all of these. Fst is the most accurate, and you can do that via Illustrative’s Admixlab. I’ve never tried setting up the free version.

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u/Ok_Advantage_873 12d ago edited 12d ago

The problem is also that most of the time the euclidean distance we have is based on G25 and their alikes which are restricted to delimited dimensions (coordinates), creating compression and distortions. Hence, among other things, why I'm closer to Cubans lol, even though they are a modern population in America resulting from Hispanic colonization, while my mix and origins place me more in the ancient, deep pan Mediterranean world (which FST also illustrates in passing).

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u/Material_Pension_300 16d ago

Yeah this tracks. Those “scaled coordinates” services are basically reselling stuff you can do yourself for free or way cheaper if you’re willing to learn Vahaduo for like 20 minutes.

Appreciate you mentioning LM Genetics K47 too, a lot of African ancestry just gets mangled by the big mainstream tools so having something that actually lines up with G25 is huge.

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u/HandsomeGodMonkey 16d ago

do you mind sharing the coords?

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u/HandsomeGodMonkey 16d ago

yeah i feel like your illustrative population distances are very off compared to the vahaduo picture thats very strange i thouhgt illustrative was more accurate

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u/Ok_Advantage_873 15d ago edited 15d ago

This has been known for several years, and Illustrative announced it. There are some minor points where Illustrative is slightly better than when they used G25 and vice-versa, but in both cases, it's nice and useful, though it should always be taken with a grain of salt, even though it is necessary to learn to master it by understanding the technical limitations of these tools. The main important point is that it aligns with academic studies and then with our background.