A multinational research team has deciphered Ludwig van Beethoven's genome for the first time using five genetically identical strands of hair.
While the study, led by the University of Cambridge, Beethoven Center San Jose, and the American Beethoven Society, KU Leuven, FamilyTreeDNA, University of Bonn, and the University of Bonn, Beethoven-Haus at Bonn and the Max Planck Institute for Evolutionary Anthropology, reveals important details about the composer's health, recent raises new questions about his past lineage and way of death.
In 1802, Beethoven asked his doctor to detail his condition and make a public record. Since then, controversy has raged about the great man's health and death, without the advantage of genetic study.
According to a study published in Current Biology, DNA from five strands of hair over the last seven years of Beethoven's life comes from a single individual, in keeping with Beethoven's known origins. After analyzing their origin histories and genetic data, experts say these five locks are "almost certainly real."
The main purpose of the study is to provide insight into Beethoven's well-known health problems, which included progressive hearing loss that began in his mid to late 20s and eventually caused him to become functionally deaf in 1818. Genetic roots of Beethoven's recurrent gastrointestinal problems and the severe liver condition that led to his death in 1827.
The composer suffered from "terrible" digestive problems that began during his time in Bonn and continued and exacerbated in Vienna.
Beethoven experienced the first of at least two episodes of jaundice, a symptom of liver disease, in the summer of 1821. It has long been assumed that his death at the age of 56 was most likely due to cirrhosis.
Health tips from Beethoven's genetics
According to scientists, Beethoven's deafness and digestive problems had no known cause. Still, they found some important genetic risk factors for liver disease. They also found evidence that the composer had been infected with the hepatitis B virus in the months before his terminal illness.
According to lead author Tristan Begg of the University of Cambridge, from the "talkbooks" Beethoven used for the last decade of his life, we can deduce that his alcohol intake was fairly regular, although it is difficult to quantify the amounts consumed. There is some disagreement between these sources, but many of their contemporaries claim that alcohol intake was moderate according to Viennese norms in the early 19th century. Regardless, this probably equated to amounts of alcohol now known to be harmful to the liver. One possible explanation for his cirrhosis is the combination between inherited risk factors and heavy enough alcohol consumption over a sufficiently long period of time.
The team also hypothesizes that Beethoven's severe liver condition, exacerbated by his alcohol consumption and genetic predisposition, may have been caused by his hepatitis B infection. The nature and timing of this disease, which could significantly affect Beethoven's association with liver disease, has yet to be determined, and scientists stress that it is still unclear how much alcohol Beethoven actually drank.
Beethoven's hearing loss has been attributed to a number of possible causes, including diseases of varying degrees of genetic origin. No direct genetic cause of hearing loss has been found following examination of the approved hair samples.
From the Institute of Human Genetics at Bonn University Hospital, Dr. According to Axel Schmidt,
“While no clear genetic cause for Beethoven's hearing loss has been found, the researchers warn that such a possibility cannot be completely ruled out. The reference data needed to interpret specific genomes is constantly getting better. Therefore, future research on Beethoven's genes is likely to provide clues as to what causes hearing loss.
Beethoven's digestive problems could not be explained genetically, but the researchers claim that genomic data makes celiac disease and lactose intolerance extremely unlikely. This is a less likely explanation because it was also discovered that Beethoven had some genetic protection against the risk of irritable bowel syndrome (IBS), the commonly putative cause.
Johannes Krause of the Max Planck Institute for Evolutionary Anthropology said: "We cannot say for certain what killed Beethoven, but we can at least confirm the presence of a significant hereditary risk and hepatitis B virus infection. We can also rule out a number of other, less likely genetic causes.
Tristan Begg adds that the amount each element is responsible for needs to be clarified in future research. “Given his known medical history, it is highly likely that it is a combination of these three factors acting together, including alcohol consumption,” he says.
All eight hair samples from public and private collections in the UK, Continental Europe and the USA were subjected to validation tests by the researchers. In doing so, researchers learned that at least two of the locks did not belong to Beethoven, including a well-known lock that was once thought to have been cut from the head of the recently deceased composer by 15-year-old musician Ferdinand Hiller.
According to previous analyzes of the "Hiller lock", Beethoven's lead poisoning may have contributed to his health problems, particularly hearing loss. "None of the previous analyzes based on this lock alone apply to Beethoven, as we now know that the 'Hiller lock' belongs to a woman and not Beethoven," said William Meredith, who led the current study with Tristan Begg. William Meredith was a member of the team involved in earlier scientific analyzes of Beethoven's remains. Future research should be based on validated samples for lead, opium, and mercury testing.
The Ira F. Brilliant Center for Beethoven Studies in San Jose, California, a private collector named Kevin Brown, and the Beethoven-Haus in Bonn have five specimens that have proven to be original and belong to the same person.
In April 1826, Beethoven personally presented one of the strands of hair now in Brown's collection to pianist Anton Halm, calling him "These are my strands." “This is my hair,” you say. Another of Brown's examples, the "Stumpff Lock", which turned out to be the best preserved, was used to sequence Beethoven's entire genome. DNA from the Stumpff lock of Beethoven's hair was most closely related to people living in modern-day North Rhine-Westphalia, consistent with Beethoven's known German ancestry.
Beethoven's Family Mystery
Researchers examined the genetic makeup of relatives living in Belgium but were unable to link any of them. Based on genealogy studies, it was determined that some had a paternal ancestor who lived in the late 1500s and early 1600s and was related to Beethoven, but did not match the Y-Chromosome found in real hair samples. The group concluded that this was most likely the result of at least one "extracouple paternity event" (a child born out of wedlock) in Beethoven's immediate paternal lineage. Maarten Larmuseau, genetic genealogist at KU Leuven, said:
“By combining DNA data and archival documents, we were able to observe that there was a discrepancy between Ludwig van Beethoven's legal and biological pedigrees.”
According to the research, this event took place in the direct paternal line between Hendrik van Beethoven's birth in Kampenhout, Belgium around 1572, and Ludwig van Beethoven's birth in Bonn, Germany, seven generations later, in 1770. The absence of a baptismal record has previously raised questions about the identity of Beethoven's father, but researchers have not been able to determine exactly in which generation this event occurred.
"We hope that by making Beethoven's genome publicly available to researchers, and perhaps adding other verified locks to the first chronological series, remaining questions about his health and pedigree can one day be answered," Begg said.
Source: phys.org/news
Günceleme: 23/03/2023 11:48