From the methods section:
> Nuclear DNA in hair has an extremely low average fragment length owing to the activity of endonucleases expressed during hair formation.
But the researchers made adjustments for that during sample prep before sequencing, and alignment after sequencing.
https://www.sciencedirect.com/science/article/pii/B978032399...
I’m not a Beethoven scholar. Is this a novel discovery?
The Wikipedia article for the composer's grandfather (who was also called Ludwig) says: in 1712 two boys named Ludwig van Beethoven were born. The two families were distantly related. [...] it is not certain "which Ludwig" actually settled in Bonn in 1733
But presumably both of those boys were officially descended from Aert so it doesn't matter for the purposes of this analysis.
That is not so uncommon in Europe. Both from my maternal and paternal line the oldest ancestors I am aware of lived almost 400 years ago, in the mid 17th century. Before that the registers from my region are very patchy, because of the devastations of the Thirty Years' War. Were this is not the case, it is not uncommon that one is able to continue the line back to the 16th century, especially for people living in towns (not to speak of the aristocracy).
Or, as another example, here is photo of the reunion of the "descendants and sides relatives of Dr. Martin Luther and Katharina von Bora" (not related to myself): https://www.lutheriden.de/the-lutheriden.html
> One Beethoven biographer63 has previously suggested, on circumstantial grounds, that Ludwig senior may not have been Johann van Beethoven’s biological father
> 63 Canisius, C. Beethoven “Sehnsucht und Unruhe in der Musik”: Aspekte zu Leben und Werk Originalausgabe. Schott, 1992
So it's been hypothesized but presumably not demonstrated genetically.