According to ESPN, Dorsett, 59, former offensive lineman Joe DeLamielleure, 62, and defensive end Leonard Marshall, 52, have underwent brain scans and other tests for the past three months at UCLA.
The test report discovered a buildup of tau, an abnormal protein that indicates CTE (chronic traumatic encephalopathy) and constricts brain cells in areas that control memory and emotions, among other functions.
The protein was also discovered in autopsies of former players Junior Seau and Mike Webster. CTE is a degenerative brain disease found in deceased athletes who have a history of repeated head trauma, including concussions or blows to the head.
CTE has been at the center of a growing crisis involving ex-NFL players and concussions, though the NFL claims there’s not enough evidence to link CTE to playing football.
The NFL denied to the dangers of concussions, and tried to cover up the links between brain trauma suffered on the football field and problems.
Dr. Bennet Omalu, one of the researchers who first identified CTE and was subsequently silenced by the NFL, is among the doctors involved in UCLA’s testing.
The condition has been discovered in dozens of former football players, including San Diego Chargers linebacker Junior Seau and Pittsburgh Steelers center Mike Webster.
Mark Duper is the ninth living former NFL player to be diagnosed with signs of CTE. There is no known cure for CTE, but Duper said, “It’s not a death diagnosis. Now I know the next step is to see what can be done. I’m not sure.”