Slovakia is one of most rich country to archeological objects and prehistory graves.
The majority of prehistory graves are bodies buried via cremation. But cremation is not probably problem for DNA for analysis, because in urn (in earthen jug/mug) are relative big pieces non-burned bones.

Archeologists in Slovakia explore approximately 5000 prehistory graves in different localities. It is large number.
Non-burned bones form prehistory graves are deposited in local museums in Slovakia (it it not public expose) .

This is old film archeological documentary from socialism langsyne. You can see jug from prehistory graves with non-burned bones. You can see cremation ceremony of funeral and bury.
https://youtu.be/_LB_XTSpVxU?t=7m11s
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If you professor on University or scientist you can with Slovak archeologist cooperation and help with genetic analysis.

Contacts to Slovak archeologiests

Slovak Academy of Sciences, archeology
https://en.wikipedia.org/wiki/Slovak...my_of_Sciences
http://archeol.sav.sk/index.php/sk/k...uradne-hodiny/
http://archeol.sav.sk/index.php/sk/o...ni-pracovnici/

University in Bratislava and Nitra, archeology
https://fphil.uniba.sk/katedry-a-odb...logie/kontakt/
https://fphil.uniba.sk/katedry-a-odb...novia-katedry/
http://www.kmuz.ff.ukf.sk/kontakt.html

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