"Ukrainians Belgorod" are actually from Berezan

[Peterski]

At least Berezan is the closest town in Google Maps to these coordinates:

https://en.wikipedia.org/wiki/Berezan,_Kyiv_Oblast

Geographical coordinates: 50.2870922, 31.5574036

https://i.imgur.com/QMypYhi.png

And Belgorod is a city in Russia, there is no such city in Eastern Ukraine.

[Ion Basescul]

At least Berezan is the closest town in Google Maps to these coordinates:

https://en.wikipedia.org/wiki/Berezan,_Kyiv_Oblast

Geographical coordinates: 50.2870922, 31.5574036

https://i.imgur.com/QMypYhi.png

And Belgorod is a city in Russia, there is no such city in Eastern Ukraine.

Maybe they referred to these and then forgot or didn't bother to zoom in properly for the exact coordinates:
https://ru.wikipedia.org/wiki/%D0%91%D0%B5%D0%BB%D0%BE%D0%B3%D0%BE%D1%80%D0%BE%D 0%B4%D0%BA%D0%B0_(%D0%9A%D0%B8%D0%B5%D0%B2%D1%81%D 0%BA%D0%B0%D1%8F_%D0%BE%D0%B1%D0%BB%D0%B0%D1%81%D1 %82%D1%8C)
https://ru.wikipedia.org/wiki/%D0%91%D0%B5%D0%BB%D0%B3%D0%BE%D1%80%D0%BE%D0%B4-%D0%9A%D0%B8%D0%B5%D0%B2%D1%81%D0%BA%D0%B8%D0%B9

[vbnetkhio]

At least Berezan is the closest town in Google Maps to these coordinates:

https://en.wikipedia.org/wiki/Berezan,_Kyiv_Oblast

Geographical coordinates: 50.2870922, 31.5574036

https://i.imgur.com/QMypYhi.png

And Belgorod is a city in Russia, there is no such city in Eastern Ukraine.

it's possible they just pinned a random point, roughly in the center of Ukraine. I'm afraid it's the case with many academic samples.
There is an Ukrainian population in Belgorod (Russia), and these samples are very similar to the Belgorod Russian academic samples, which were also sampled, so I think they are more likely from there.