New study shows CTE could be caused by your genes

Scientists have been studying our genetic code to better determine why some people develop chronic traumatic encephalopathy, the Alzheimer’s-like disease that has been associated with sports and repeated hits to the head. Boston University’s CTE Center reports that a variant gene TMEM106B could influence why some people experience more severe forms of the disease than other in a newly released study.

“Among people who have CTE, people with this [genetic] variation are 2.5 times more likely to develop dementia,” said Dr. Jesse Mez, assistant professor of neurology at Boston University’s School of Medicine. Mez was a co-author of the study, published Saturday in the journal Acta Neuropathologica Communications.

The findings, though early Mez says are a step in the right direction in better understanding the disease.

“It helps us better understand biologically, mechanistically, what is going on in the brain in CTE. In understanding the mechanism and in identifying this genetic risk factor, we have new potential targets to develop therapies,” he said.

The authors do point out that their findings need to be further investigated in a larger group and the replicated to make any definitive conclusions.

Not Ready For Primetime

Dr. Sam Gandy a professor of neurology and psychiatry and director of the Center for Cognitive Health at Mount Sanai in New York, said the findings were simply too premature and couldn’t account for other genes that may be involved in the disease, like APOE4.

Gandy who was not involved in the study wrote in an email that the findings were “not ready for prime time.”

Dr. Bennet Omalu, the pathologist who first detected CTE in professional football players, agreed that it was too early to make much of the findings.

“We need to tread carefully. The study shows that the gene may be associated with reduced risk for CTE, but CTE is a polymorphous and polyphenotypic and polygenetic disease, [and] focusing on one gene, which may reduce risk, may be a stretch,” Omalu, who was also not involved in the new research, wrote in an email.

Mez and his team at Boston University are also looking at other genes that may play a role in CTE. “If these other genes do not have an effect, it will likely be independent and additive with the TMEM findings.”

Mez added that it is “likely several  genes across the genome that contribute to CTE risk and severity, and in the future, considering all of them together will improve our predictive capability.”

Today, CTE can be only be diagnosed after death. It is believed to result from repeated head trauma. In football, this can happen not just from hard hits to the head that results in concussion but from the repeated rattling of the brain inside the skull during tackles and falls to the turf. These repeated hits are known as subconcussive hits that can result in a buildup of a kind of protein called tau in the brain. Early and longer exposure to treat trauma is also considered to be a likely contributor to the disease.

Gene Tied to Less-Severe CTE

“Among just those with CTE, that CTE-related outcomes were more severe, they were more likely to have dementia, and they were more likely to have advance neurodegeneration in their brain,” Mez said.