You're more likely to get Alzheimer's if your mom has it, says study

You're more likely to get Alzheimer's if your mom has it, says study

• READ MORE: Scientists find genetic trait that almost GUARANTEES Alzheimer's

You may be more likely to develop Alzheimer's if your mother has been diagnosed with the disease, compared to if your father has suffered it, a new study suggests.

However, those who have fathers diagnosed with the degenerative condition early — before the age of 65 years — may also be at higher risk of developing the disease than the average patient.

Researchers in Massachusetts made the discovery after analyzing brain scans of 4,400 adults with an average age of 70, and with no cognitive impairments.

Each brain was scanned for amyloid plaques — a build-up of toxic protein thought to be a precursor of Alzheimer's, the most common form of dementia.

Researchers found those with higher levels of plaques in the brain tended to have a family history of the disease on their mother's side.

However, higher-than-average amyloid levels were also seen on the brains of those who had fathers that were diagnosed with Alzheimer's at 65 or younger.

Amyloid plaques are thought to trigger the disease by disrupting communications between brain cells, stopping the organ functioning correctly.

They build-up silently over time and can be in the brain for years before any symptoms of the disease occur.

The researchers suggested patients with mothers who had dementia could be at greater risk because of specific mitochondria, tiny structures in cells that make energy.

These are only inherited from the mother but carry their own DNA, including any mutations that may predispose them not to work properly.

Researchers also theorized that the risk may be to do with faults in the X chromosome, which is always passed down by the mother.

Fathers can also pass down an X chromosome, making their offspring female, however this only happens in 50 percent of newborns.

Fathers with early-onset Alzheimer's may also raise the risk for their children because they could have a strong genetic predisposition to the disease, the researchers said.

Dr Hyun-Sik Yang, a neurologist at Mass General Brigham who led the research, said: 'Our study found if participants had a family history on their mother's side, a higher amyloid level was observed.'

'If your father had early onset symptoms, that is associated with elevated levels in the offspring,' added neurologist Dr Mabel Seto, who was also involved with the study.

Alzheimer's disease affects some 7million Americans and is the 7th leading cause of death in the US.

The condition is thought to be a largely inherited disease, with between 60 and 80 percent of patients having a family history, according to studies.

Those who have a parent or relative with the disease are thought to be between two to 15 times more likely to develop the condition, depending on the number of relatives affected.

Previous studies have also found that the maternal line may be more impactful than the paternal for passing on disease.

Among celebrities who have revealed a history of Alzheimer's in their family is Peter Gallagher, who cared for his mother after she was diagnosed with the disease at the age of 69 years for two decades.

He previously said: 'An Alzheimer's diagnosis can be as devastating to the caregiver as to the person diagnosed.'

Chris Hemsworth has also revealed a family history of the disease, saying his grandfather suffered from Alzheimer's. His 68-year-old father has also reported that he is suffering from early symptoms of the disease.

Hemsworth has revealed that he is genetically predisposed to be more likely to develop the disease.

For the latest paper, published today in JAMA Neurology, researchers extracted data from the Anti-Amyloid Treatment in Asymptomatic Alzheimer's (A4) study.

This involved scanning the brains of adults at sites in the US, Europe and Japan between April 2014 and December 2017 for amyloid plaques.

Patients were mostly from non-white ethnic backgrounds, researchers said, which may have impacted the results.

Adults were not tracked for years after the study, so it was not clear how many actually went on to develop dementia.

Brain scans were compared to reports of family history of the disease from patients to reveal associations.

Although amyloid plaques are the leading hypothesis for the cause of dementia, others suggest they their role is less important, instead pointing to damage to blood vessels as being the main cause.

It is expected that the number of adults with Alzheimer's Disease in the US will surge to 12.7million by 2050 due to the aging population and increasingly unhealthy lifestyles.

The disease normally begins in the mid 70s, although in rare cases it can occur in those in their 40s and 50s.

Symptoms begin as trouble remembering recent events or conversations, repeating questions or difficulties remembering where you've put things.

In later stages, the disease causes loss of awareness of surroundings, an inability to communicate coherently and difficulty swallowing or eating.