The 2023 study found that Beethoven’s genome carried significant genetic risk factors for liver disease. The specific variants identified placed him at elevated heritable risk for the kind of hepatic dysfunction that, in combination with heavy alcohol use, could produce progressive liver damage and eventual cirrhosis. This finding does not constitute a diagnosis; it establishes a predisposition. A person with this genetic profile might never develop liver disease if they lived differently. But in combination with the level of alcohol consumption the historical record attributes to Beethoven, the genetic susceptibility makes the cirrhosis diagnosis considerably more plausible.
Then the researchers found something else in the genetic material: evidence of hepatitis B infection.
Markers consistent with hepatitis B viral DNA were detected in the hair samples. The researchers concluded that Beethoven had experienced a hepatitis B infection at some point, and that based on the timing of the samples—most of which were cut in the seven years before his death—the infection was likely present in the months before his final illness. Whether the infection was a recent acute exposure or a chronic condition that had been ongoing for years could not be determined from the genetic evidence available.
Hepatitis B is a viral infection that can cause severe liver damage, including cirrhosis and liver failure, particularly in individuals who carry it chronically. The combination of genetic susceptibility to liver disease, heavy alcohol consumption, and a hepatitis B infection represents, in the assessment of Christian Strassburg, a liver disease specialist at the University Hospital Bonn who contributed to the study, a convergence of factors that could plausibly account for the severity and trajectory of Beethoven’s terminal illness.