FROM CNN WIRES:
Los Angeles (CNN) - An insidious, microscopic protein that has been found in the brain tissue of professional football players after death may now be detectable in living people by scanning their brains.
Researchers say they found tau protein in the brains of five living retired National Football League players with varying levels of cognitive and emotional problems.
"It's definite, we found it, it's there," said Dr. Julian Bailes, co-director of the NorthShore Neurological Institute in Evanston, Illinois, and co-author of a new study that identified the tau. "It was there consistently and in all the right places."
This morning on "Early Start," CNN's Sanjay Gupta explains the study which could have major implications for football players.
READ MORE: Scan may detect signs of NFL players' brain disease
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