Alzheimer’s disease slowly erodes memory, independence, and the ability to connect with loved ones. It is the most common cause of dementia, affecting millions worldwide. A recent study published in JAMA Neurology reveals that the maternal side of the family more strongly influences the risk of developing Alzheimer’s than the paternal side.
The study found that people with mothers who had a history of memory problems showed higher levels of beta-amyloid, a key protein linked to Alzheimer’s. The same pattern did not hold for those with fathers who developed late-onset memory loss.
However, if a father experienced memory decline before age 65, the risk of Alzheimer’s increased significantly.
The Study Analyzes Over 4,400 Participants
The researchers analyzed data from 4,413 people aged 65 to 85 who had no signs of cognitive decline. These participants were part of a clinical trial investigating a drug aimed at slowing memory loss.
By scanning their brains using positron emission tomography (PET), the researchers assessed amyloid plaque buildup - one of the hallmarks of Alzheimer’s disease. Amyloid plaques form when beta-amyloid proteins clump together, disrupting normal brain function.
Nino / Pexels / Analyzing 4,400 participants, the study found that participants whose mothers had memory issues had higher levels of this protein.
This suggests that maternal history plays a more significant role in Alzheimer’s risk than paternal history.
Why Alzheimer’s Has the Maternal Connection
One possible reason for this maternal influence lies in mitochondrial DNA. Unlike nuclear DNA, which is inherited from both parents, mitochondria are passed down exclusively from mothers. These tiny structures produce energy for cells, including neurons.
When they malfunction, brain function can suffer, potentially increasing the risk of Alzheimer’s.
Previous studies have already linked mitochondrial dysfunction to Alzheimer’s disease. Since the brain requires a massive amount of energy to function properly, any disruption in mitochondrial performance could contribute to cognitive decline. This could explain why Alzheimer’s risk appears to be higher when the disease runs on the maternal side.
Early-Onset Memory Loss and Alzheimer’s Risk
Although the study showed a stronger link between maternal history and Alzheimer’s, it also found that early-onset memory loss in fathers (before age 65) increased risk as well. This suggests that genetic and environmental factors on both sides of the family can play a role.
On the other hand, participants with fathers who developed memory issues later in life did not show elevated beta-amyloid levels. This indicates that late-onset memory decline in fathers may not carry the same genetic risk as maternal memory loss or early-onset paternal memory loss.
Ivan / Pexels / While genetics play a role, lifestyle factors like diet, exercise, and mental stimulation also impact Alzheimer’s risk.
What This Means for Alzheimer’s Prevention
Understanding the genetic influence of Alzheimer’s can help researchers develop better diagnostic tools and preventive strategies. If a person’s risk is higher due to maternal history, they may benefit from earlier screenings or lifestyle changes aimed at protecting brain health.
Those with a family history - especially on the maternal side - should focus on healthy habits to support brain function and delay potential cognitive decline.
This study sheds light on an important factor in Alzheimer’s risk, but more research is needed. Since most study participants were white, the findings may not apply to all ethnic groups. Future research should include more diverse populations to ensure these patterns hold across different backgrounds.
