Whether the letter’s wish was ever fulfilled is a matter of perspective. The 2023 study identified risk factors for liver disease, found evidence of hepatitis B infection, and excluded several proposed causes of his gastrointestinal problems and his deafness. It did not deliver the complete picture Beethoven may have hoped for. But it moved the understanding of his health considerably further than any previous investigation.
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## The Y-Chromosome Finding and What It Does—and Doesn’t—Mean
Of all the results in the 2023 study, the Y-chromosome finding has generated the most popular attention and the most careful hedging from the researchers themselves.
The finding required an additional step beyond Beethoven’s genome: comparison with living people. The study’s team worked with genetic genealogist Maarten Larmuseau of KU Leuven and used data from FamilyTreeDNA to identify living men whose documented paternal lineages—traced through records of births, marriages, and family names—intersected with Beethoven’s paternal lineage at a common ancestor in Belgium.
Beethoven’s family was Flemish in origin. The name “van Beethoven” traces to the Belgian village of Mechelen and to a lineage that can be followed through documented records back to at least the sixteenth century. The study identified living men whose paternal-line ancestry shared an ancestor with Beethoven from the period running from the late 1500s to the early 1600s. This shared ancestor was Hendrik van Beethoven, who was born in Kampenhout, Belgium, in approximately 1572.
When the researchers compared the Y chromosomes of these living relatives against the Y chromosome extracted from the authenticated Beethoven hair samples, the chromosomes did not match.