Chronic traumatic encephalopathy (CTE) - a neurodegenerative disease diagnosed after death, most often in athletes who played contact sports and in military personnel - is not just caused by repeated head impact but also linked to DNA damage similar to that seen in Alzheimer's disease, according to a new study led by researchers at Harvard Medical School, Boston Children's Hospital, Mass General Brigham, and Boston University.
- By JOELLE ZASLOW | Boston Children's
CTE is known to share characteristics with Alzheimer's disease, namely the buildup of abnormal tau protein in the brain. CTE has also been associated with the development of dementia. The new research, published Oct. 30 in Science, highlights the commonalities between CTE and Alzheimer's at the genetic level and raises hopes that future treatments could target both diseases.
The findings also support recent work from study co-authors Jonathan Cherry and Ann McKee at Boston University in suggesting that immune system responses could help explain why only some people with repeated head impact go on to develop CTE.
"Our results suggest that CTE develops through some process in addition to head trauma," said co-senior author Christopher A. Walsh, the HMS Bullard Professor of Pediatrics and Neurology and chief of the Division of Genetics and Genomics at Boston Children's. "We suspect it involves immune activation in a way similar to Alzheimer's disease, happening years after trauma."
A new approach to studying CTE
The team used two types of single-cell genomic sequencing to identify somatic genetic mutations - changes in DNA that occur after conception and are not inherited from the parents. This marked the first time scientists took such an approach to studying CTE.
Studying postmortem brain tissue samples, the researchers analyzed hundreds of neurons from the prefrontal cortex of 15 individuals diagnosed with CTE after death and 4 individuals with repeated head impact but without CTE and compared them with 19 neurotypical controls and 7 individuals with Alzheimer's.
