Almost two centuries ago, on March 26, 1827, one of the most influential composers of classical music, Ludwig van Beethoven, died in Vienna at the age of 56. Since then, debates about the exact reasons for his death have never ceased among specialists. Today researchers have been able to use an unprecedented technique to shed new light on the untimely death of the German composer: the turning point came by analyzing his DNA obtained from 5 strands of hair, which scientists received thanks to some collectors, dating back to his last 7 years of life and attributed to the composer with a wide margin of safety.

According to the study, published in the journal Current Biology by an international research team led by the German Max Planck Institute and the British University of Cambridge, Beethoven's death was certainly due to cirrhosis and not from lead poisoning as had been believed until now. Cirrhosis was the result of a series of chronic gastrointestinal disorders, caused by possible celiac disease and lactose intolerance and linked to genetic risk factors for liver disease, as well as alcohol consumption and hepatitis B that the famous composer would have contracted in the last months of life.

The main aim of the study, led by Tristan Begg of the Max Planck Institute and University of Cambridge, was to shed light on Beethoven's health problems, which are known to include progressive hearing loss and chronic gastrointestinal disorders.

Getting the genes for the researchers has been a challenge since the DNA in the hair is broken down into tiny fragments, explained Johannes Krause, a paleogeneticist at the German Max Planck Institute for Evolutionary Anthropology. Beethoven's hair was cleaned one strand at a time before being analyzed, and then scientists dissolved it in a solution from which they fished out pieces of DNA, Tristan Begg added.

To make sure they were working with the German composer's DNA, the researchers conducted authentication tests on eight hair samples from public and private collections in the UK, Europe and the US. They discovered that at least two of the stored locks were not authentic, including one believed to have been cut by fifteen-year-old musician Ferdinand Hiller from Beethoven's recently deceased head. Nicknamed the 'Hiller lock', his previous analysis supported the hypothesis that Ludwig suffered from lead poisoning, which could explain his health problems, including hearing loss: the lock turned out to belong to a woman.

The key question of what caused Beethoven's hearing loss remains unanswered. Axel Schmidt from the Institute of Human Genetics at the University Hospital Bonn said: "Although it has not been possible to identify a clear genetic basis for Beethoven's hearing loss, we warn that such a scenario cannot be strictly ruled out. Baseline data, which are mandatory to interpret individual genomes, are constantly improving. It is therefore possible that Beethoven's genome will reveal clues about the cause of his hearing loss in the future."

From examination on Y chromosome discovered extramarital relationship in the family tree of the composer

The research also led to a surprising discovery: when they tested the DNA of living members of Beethoven's extended family, scientists discovered a discrepancy in the Y chromosomes that are passed down from the father's side. The Y chromosomes of the five men corresponded to each other, but did not correspond to those of the composer. This suggests that there was an "extra-marital paternity event" somewhere in the generations before Beethoven's birth, Begg said. In other words, a child born of an extramarital affair in the composer's family tree.