Researchers have found a potential gene variant that helps certain people cope with Alzheimer's disease.

The study, conducted by researchers at Vanderbilt University Medical Center, found a genetic variant that might explain why some people are more resilient and don't show symptoms of Alzheimer's disease despite having biomarkers of the disease.

Alzheimer's disease is a common form of dementia affecting older people. People with AD have problems performing everyday tasks. The new study suggests that there might be genes that prevent some people from developing symptoms even though the brain has proteins associated with the disease.

"Most Alzheimer's research is searching for genes that predict the disease, but we're taking a different approach. We're looking for genes that predict who among those with Alzheimer's pathology will actually show clinical symptoms of the disease," said principal investigator Timothy Hohman, Ph.D., at the Vanderbilt Memory and Alzheimer's Center.

In the study, researchers focused on a biomarker called phosphorylated tau. This protein is required for normal brain functioning. However, in some people tau forms tangles and disrupts the brain signals.

The research included 700 patients from the Alzheimer's Disease Neuroimaging Initiative. The study team looked at the gene variants that were linked to the relationship between tau and severity of the disease.

They found that one mutation called rs4728029 was associated with symptoms of the disease.

"This gene marker appears to be related to an inflammatory response in the presence of phosphorylated tau," Hohman said in a news release. "It appears that certain individuals with a genetic predisposition toward a 'bad' neuroinflammatory response have neurodegeneration. But those with a genetic predisposition toward no inflammatory response, or a reduced one, are able to endure the pathology without marked neurodegeneration."

Hohman plans to expand the research by including a larger sample size to understand the role of the genetic variant.

The study is published in the journal Alzheimer's and Dementia.

Data from the Alzheimer's Association shows that over 5 million people in the U.S. have AD. There is no cure for the disease. Understanding the genetic basis of the disease will hopefully lead to better therapeutics for the condition.