Beethoven's DNA Has Been Analyzed After 200 Years From Locks of Hair

In a finding almost 200 years in the making, researchers have analyzed Beethoven’s DNA using samples of hair to better understand the ailments that famously plagued the composer.

The researchers' analysis shows that neither his hearing loss nor his frequent stomach issues were caused by Beethoven's genes. However, the liver disease that ultimately led to his death probably did have a genetic basis and was spurred on by a lingering hepatitis B infection. 

Plus, in a surprising twist that came about through the genetic analysis and reconstructing potential family trees, researchers have uncovered that someone on Beethoven’s father’s side had an extramarital affair resulting in a child. It may even have been Beethoven’s father, potentially making Beethoven an illegitimate son.

The work was inspired by a wish Beethoven made in an 1802 document, where he requested that doctors investigate the cause of his hearing loss and that the findings be made public. The study is published today in Current Biology.

Probably the most well known of Beethoven’s health problems is his hearing loss—which led Beethoven to shutter himself away and contemplate suicide. But the artist was also plagued with bouts of pain in his ribs and gut and extreme weakness stemming from issues with his digestive system, as well as jaundice from his failing and scarred liver. 

Medical biographers have previously pieced together a picture of Beethoven’s health mostly from letters he wrote and diaries he kept, as well as written accounts from his physician and an autopsy report following his death. Some have also performed chemical analysis on the composer’s hairs and bits of his skull. Some of these samples have been deemed inauthentic.    

“Beethoven really is kind of unique because of the enormous literature on his health problems. So it was really a unique chance to use molecular genetic methods to add something to this,” said study coauthor and geneticist from the University of Bonn, Markus Nöthen, in a press briefing.

In this latest study, researchers analyzed DNA from eight locks of Beethoven’s hair—totally some three meters in length. They verified the authenticity of five of these fragments both by tracking who looked after the hairs over time, the provenance histories, and looking closely at features of the DNA itself, like that the damage matches up to the expected age of the samples.

Researchers couldn’t link Beethoven’s hearing or gut problems with his genes. However, they didn’t totally rule out a genetic cause. 

“Unlike in ancient bones, DNA in ancient hair is highly degraded, so we have very short fragments of DNA,” said coauthor Johannes Krause from the Max Planck Institute for Evolutionary Anthropology in a press briefing. This meant Nöthen, Krause and his team weren’t able to sequence Beethoven's entire genome and their analysis couldn't detect some particular genetic mutations. “It’s really hard to get enough DNA from hair to assemble a genome,” said Krause.

That means other theories surrounding Beethoven’s notable hearing loss still linger. One is otosclerosis, where a spongy boney nub grows in the middle ear and prevents the ear bones from vibrating properly. Another is Paget’s disease, where the ear bones become more fragile. 

These diseases (and a host of other possibilities) might have a genetic aspect to them. But study coauthor Tristan Begg, a PhD student in biological anthropology with the Max Planck Institute for the Science of Human History, said they couldn’t test this theory. “We didn’t have sufficient reference data to actually assess Beethoven’s risk for otosclerosis but it has to be stressed that the diagnostic accuracy for assessing otosclerosis would not be great, it would just be a start.”

The team did, however, find that Beethoven’s genes predisposed him to liver disease. They also detected fragments of DNA from the hepatitis B virus that had become lodged in the hair strands. “It tells us that, at least in the last few months before his death, he was infected with hepatitis B. It could have been earlier,” said Krause.

Putting all the information together, the researchers think that Beethoven’s liver disease was caused by a mix of his genes, his well-documented and long-running alcoholism, and the hepatitis B virus—a virus that’s spread through sex but also through sharing needles or during pregnancy (there’s no evidence to say how Beethoven became infected). 

Davide Brotto, a medical doctor specializing in audiology and who wasn’t involved in the study, told Motherboard that this study confirms what he and his colleagues suspected in a previous study—that the liver was involved in many of Beethoven’s underlying health problems. “From what I get Beethoven was a person with fragile genetics and a fragile liver that got worse because of his alcoholic attitude. This explains his gastrointestinal symptoms and the hearing loss as well, and also the composer’s behavioral issues.”

There are of course limits to what researchers can glean about Beethoven's health issues. “A great problem in medicine is the subjective perception of the symptom, which makes it difficult to be understood by a physician,” said Brotto. Like others writing on Beethoven’s illnesses, Brotto and his team relied on historical records and letters between Beethoven and his doctor, however Brotto notes that “some of these reports may be biased by his psychological status, by his frustration of not getting a good diagnosis and also the limitations of the medical knowledge in the time he lived in.”

Then there are the things that don’t show up in letters, such as the euphemistically dubbed “extra-pair paternity event” this latest study uncovered. The finding came about when researchers analyzed Y chromosomes from five living descendents of the Beethoven lineage. These genetics could be traced back to an ancestor who lived in the 16th century. However, when the team compared Beethoven’s Y chromosome to those of his living descendents, they didn’t match. That told researchers that some time in the seven generations between that 16th century ancestor and Beethoven’s birth, someone had an affair resulting in a child. “You wouldn’t necessarily expect such an event to be documented. These would probably be clandestine in nature,” said Begg.

It may have been Beethoven’s father, although Begg and his colleagues aren’t weighing in one way or the other. “If you are completely agnostic to the historical record and you know there has been an extra pair paternity event at some point in the seven generations above Beethoven, you cannot rule out that Beethoven himself may have been illegitimate,” said Begg. “I’m not advocating for that, I’m simply saying it’s a possibility.”