In 2011 former NFL safety Dave Duerson committed suicide by a gunshot to his chest. He had sent a text message to his family saying he wanted his brain to be used for research at the Boston University School of Medicine, which is conducting research into chronic traumatic encephalopathy (CTE). Neurologists at Boston University confirmed that Duerson suffered from CTE.
In 2012 former NFL linebacker Junior Seau committed suicide by a gunshot to his chest. Neurologists at the National Institute of Neurological Disorders confirmed that Seau suffered from CTE.
In 2006 former NFL safety Andre Waters committed suicide by gunshot. Neurologists confirmed that Waters suffered from CTE.
Wikipedia’s list of confirmed suicides is long: