Muhammad Ali died Friday with the Parkinson’s disease that helped define his life for the last 32 years.
Boxing may have contributed to his illness, but genetics was likely a bigger factor, experts said. “It’s bad luck on top of genetics,” said Ole Isacson, a professor of neurology at Harvard Medical School who met Ali several times. People who lose consciousness through head trauma are at 50% higher risk of Parkinson’s than those who don’t, he said.
Ali’s symptoms and the course of his disease were also consistent with a genetic form of Parkinson’s, said Michael Okun, chairman of neurology at the University of Florida, who was a longtime Ali friend and adviser. About 10% of cases are believed to be caused directly by genetics.