The belief is that Ludwig van Beethoven's grandmother may have had an extramarital relationship which led to the birth of his father, says Maarten Larmuseau, a co-author of the study and a professor of genetic genealogy at the University of Leuven in Belgium.
Researchers were not able to find answers relating to Beethoven's mysterious hearing loss that occurred in his 20s, or the gastrointestinal problems which plagued him throughout his life, but they did rule and lactose intolerance as unlikely causes.