Genetics can play a role in a person's odds for Alzheimer's disease, and new research suggests differences in that risk are based on which parent had the illness.
In a study of 4,400 people still "cognitively unimpaired," there was higher buildup of amyloid protein plaques in the brain (a hallmark of Alzheimer's) if either the person's mother, or both parents, had Alzheimer's, compared to folks where Alzheimer's had only struck the father.
People with an Alzheimer's-affected mother may therefore be at special risk, said a team from Mass General Brigham, in Boston.
"Maternal inheritance of Alzheimer's disease may be an important factor in identifying asymptomatic individuals for ongoing and future prevention trials,"said study co-author Dr Reisa Sperling, a neurologist at Mass General.
The findings were published June 17 in the journal JAMA Neurology.
The study was based on data from a clinical trial focused on Alzheimer's prevention. People in the study were asked about whether or not either of their parents had ever been diagnosed with Alzheimer's disease, and when their parent's memory began to fail.
Sperling and colleagues then compared those answers to levels of amyloid in people's brains.
Having had a father who developed Alzheimer's symptoms relatively late in life did not seem to be related to levels of amyloid in people's brains, the research showed.
However, there was a correlation between the accumulation of brain plaques and having had a mother whose Alzheimer's symptoms began at any age, or having a father whose symptoms began relatively early, the team reported.
"If your father had early-onset symptoms, that is associated with elevated [amyloid] levels in the offspring,"said study first author Dr. Mabel Seto, a postdoctoral research fellow in the hospital's department of neurology. "However, it doesn't matter when your mother started developing symptoms -- if she did at all, it's associated with elevated amyloid."
The sex of the study participant did not seem to matter when it came to the relationship between amyloid buildup and parental histories, the researchers noted.
"It's also important to note a majority of these participants are non-Hispanic white,"Seto added in a Brigham news release. "We might not see the same effect in other races and ethnicities."
More information
Find out more about Alzheimer's disease and genetics at the Alzheimer's Association.
SOURCE: Mass General Brigham, news release, June 15, 2024
