Brain of dead NFL gunman Phillip Adams to be examined for CTE by experts trying to uncover truth behind horrific US murder spree

The brain of ex-NFL star Phillip Adams is to be examined for the degenerative disease CTE, with investigators searching for answers around the horrific shooting spree which claim the lives of five people and the late player.

Coroner Sabrina Gast announced on Friday that Adams' brain will be probed for signs of CTE when his autopsy is performed at the Medical University of South Carolina, per a report by WSOC-TV.

The development comes just days after Adams was named as the suspected gunman in a shooting which cost the lives of prominent South Carolina medic Dr Robert Lesslie, his wife Barbara and two of their grandchildren, aged nine and five. 

A fifth person, James Lewis, 38, who is understood to be an air conditioning contractor working on Dr. Lesslie's home, was also killed. A sixth victim was also transported to hospital with what was described as a "serious gunshot wound".

Adams, 32, killed himself in his nearby parents' residence some time after allegedly storming the Lesslies' home in the violent incident. Unconfirmed reports online indicate that Adams was a previous patient of Dr. Lesslie's. 

Almost immediately after the shooting spree, questions were raised about the potential role that CTE may have played in the shootings. The brain disorder has been found to be prevalent amongst players in full-contact sports such as the NFL, with a recent study showing the disease was present in 110 or 111 ex-NFL players who were tested.

The potential impact of the condition on NFL players has been a bubbling undercurrent in the sports in recent years, with the league recently agreeing to pay $1 billion as part of a package to players who say that they were kept in the dark about the potential health impacts of a career on the gridiron.

CTE was also cited as a factor in murders involving ex-NFL players Aaron Hernandez and Jovan Belcher.

Adams is understood to have suffered several concussions during his six-season stint in the NFL, where he represented the likes of the San Francisco 49ers, New England Patriots and Atalanta Falcons.

Speaking to USA Today, Adams' sister noted how they had witnessed an alarming turn in him in recent times, saying that his "mental health degraded fast and terribly bad" and that she had noticed "extremely concerning" examples of his well-being.

His father previously told TMZ Sports this week that his son was a "good kid" but that "football messed him up".

Adams' former agent, Scott Casterline told AP that his client was unwilling to participate in schemes designed by the league to safeguard players' mental health.

"We encouraged him to explore all of his disability options and he wouldn’t do it," he said, while also indicating that an ankle injury suffered by the player in 2010 severely hampered his NFL career.

"I knew he was hurting and missing football but he wouldn’t take health tips offered to him. He said he would, but he wouldn’t."