Report: Junior Seau suffered from CTE

Former San Diego Chargers, Miami Dolphins and New England Patriots linebacker Junior Seau, who blazed a Hall of Fame trail through 20 NFL seasons from 1990 through 2009, committed suicide in May 2012. It was a surprise to everybody, and we may now know more of the reason behind Seau's tragic end. According to an exclusive report from ABC News/ESPN, Seau was found to have suffered from Chronic Traumatic Encephalopathy, a neurodegenerative condition that can lead to memory loss, dementia and depression.

Seau's family donated his brain to the National Institutes of Health in Washington, D.C., to find out if he was one of many players whose time in the NFL led to CTE. Seau's widow, Gina, said that last week, doctors told her that he did.

"I think it's important for everyone to know that Junior did indeed suffer from CTE," Gina Seau said. "It's important that we take steps to help these players. We certainly don't want to see anything like this happen again to any of our athletes."

[Rewind: Junior Seau's death further saddens his 1994 Chargers teammates]

Dr. Russell Lonser, the former chief of surgical neurology at the NIH, said that because of the publicity surrounding Seau's death, Seau's brain was "blinded" during research so that nobody doing the diagnosis would know whose brain they were studying.

"The neuropathologists each examined tissue samples from three different unidentified brains. The official, unanimous diagnosis of Mr. Seau’s brain was a 'multi-focal tauopathy consistent with a diagnosis of chronic traumatic encephalopathy,' the NIH said in its statement. "In addition, there was a very small region in the left frontal lobe of the brain with evidence of scarring that is consistent with a small, old, traumatic brain injury.

"Specifically, the neuropathologists found abnormal, small clusters called neurofibrillary tangles of a protein known as tau within multiple regions of Mr. Seau’s brain. Tau is a normal brain protein that folds into tangled masses in the brain cells of patients with Alzheimer’s disease and a number of other progressive neurological disorders. The regional brain distribution of the tau tangles observed in this case is unique to CTE and distinguishes it from other brain disorders.

"The type of findings seen in Mr. Seau’s brain have been recently reported in autopsies of individuals with exposure to repetitive head injury, including professional and amateur athletes who played contact sports, individuals with multiple concussions, and veterans exposed to blast injury and other trauma.

Gina Seau said that the diagnosis was not a surprise. "The difference with Junior ... from an emotional standpoint [was] how detached he became emotionally," she said. "It was so obvious to me because early, many, many years ago, he used to be such a phenomenal communicator. If there was a problem in any relationship, whether it was between us or a relationship with one of his coaches or teammates or somewhere in the business world, he would sit down and talk about it."

Seau's son Tyler agreed. "He would sometimes lose his temper. He would get irritable over very small things. And he would take it out on not just myself but also other people that he was close to. And I didn't understand why."

[Rewind: Junior Seau was gregarious, ebullient, hilarious and immensely popular]

In his 20-year NFL career, Seau was never listed as having a concussion on any medical or injury report. He shot himself in the heart, some speculated, so that his brain would be available for study after his death. Chicago Bears defensive back Dave Duerson shot himself in the chest in February 2011 and left a specific request that his brain be left to the Boston University School of Medicine.

The league is currently a potential defendant in lawsuits filed by more than 4,000 former players, a full third of the number of living former players, according to NFLConcussionLitigation.com. The players claim that the league knew of the dangers of concussions and did not diagnose them, leading to horrific post-football lives for many of its players. The Seau diagnosis, and the way in which Seau ended his life, will be a major blow to the NFL in the court of public opinion.

[Related: NFL shows disconnect in statement on Junior Seau's CTE condition]

"We appreciate the Seau family’s cooperation with the National Institutes of Health," the NFL said in a statement in response to the diagnosis. "The finding underscores the recognized need for additional research to accelerate a fuller understanding of CTE. The NFL, both directly and in partnership with the NIH, Centers for Disease Control and other leading organizations, is committed to supporting a wide range of independent medical and scientific research that will both address CTE and promote the long-term health and safety of athletes at all levels. The NFL clubs have already committed a $30 million research grant to the NIH, and we look forward to making decisions soon with the NFL Players Association on the investment of $100 million for medical research that is committed in the Collective Bargaining Agreement. We have work to do, and we’re doing it."

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