Beheaded French King
The scientists said the DNA is very similar to genetic material from what is believed to be the mummified head of an earlier French king, AFP reports.
After Louis XVI's beheading many spectators were reported to have dipped their handkerchiefs in his blood.
The piece of fabric had been placed in a dried, hollowed-out gourd, leaving blood stains.
The squash was decorated with images of revolutionary heroes and the words: "On January 21, Maximilien Bourdaloue dipped his handkerchief in the blood of Louis XVI after his decapitation".
The revolutionary souvenir has been in the hands of an Italian family for a century.
Read more: bbc