Scientists may be one step closer to a cure for Alzheimer’s after determining who is most likely to contract the disease.
Researchers have found that almost all individuals with two copies of a particular gene, called APOE4, develop signs of this memory-robbing condition.
Previously, the quirk, carried out by Avengers star Chris Hemsworth, had been linked to a tenfold risk.
The team at the Sant Pau Research Institute in Barcelona analyzed clinical data from more than 10,000 people and more than 3,000 brain donors.
They found that more than 95 percent of people aged 65 and older who had two copies of the APOE4 gene showed early signs of the disease.
Researchers have found that almost all individuals with two copies of a particular gene, called APOE4, develop signs of this memory-robbing condition. Previously, the quirk, carried out by Avengers star Chris Hemsworth, had been linked to a tenfold risk.
Alzheimer’s disease is the most common cause of dementia. The disease can cause anxiety, confusion and short-term memory loss.
These people also developed the condition earlier than those with other variants of the gene, the researchers said.
They believe this is the first study to show that having two copies of APOE4 almost guarantees the onset of the disease.
The team said their discovery is especially important since about 2 percent of the population carries two copies of this gene.
And it could identify the best people to include in clinical treatment trials.
Dr. Juan Fortea, director of the neurological diseases, neuroscience and mental health research area at the Sant Pau Research Institute, states: ‘These data represent a reconceptualization of the disease or what it means to be homozygous for the APOE4 gene.
“This gene has been known for more than 30 years and was known to be associated with an increased risk of developing Alzheimer’s disease.
“But now we know that virtually all individuals with this duplicated gene develop Alzheimer’s biology.”
The APOE gene comes in three different variations: APOE2, APOE3 and APOE4.
Everyone carries two copies of the APOE, one inherited from each parent. Previous studies have shown that having at least one variant of the APOE4 gene, which is thought to be carried by around a quarter of people in the UK, almost triples the risk of contracting the disease.
The new research showed that by age 65, almost all people who had two copies of APOE4 had abnormal levels of a protein known as amyloid in the fluid surrounding the brain and spinal cord, a key sign of Alzheimer’s.
Dr. Reisa Sperling, a professor of neurology at Harvard Medical School and director of the Alzheimer’s Research and Treatment Center at Brigham and Women’s Hospital in Boston, Massachusetts, said, “We have to think about how we can treat carriers of APOE4.
‘These people are desperate: they have seen (the disease) in both of their parents.
“This research really suggests that we should treat them quite early, at a younger age and at an early stage of the pathology because we know that they are very likely to progress rapidly to deterioration.”
Commenting on the findings, Professor Tara Spiers-Jones, president of the British Neuroscience Association, said: “This study adds compelling data suggesting that people with two copies of this gene are almost certain to develop Alzheimer’s if they live long enough and will live enough”. develop Alzheimer’s earlier than people without this gene.
“Looking ahead, this study and others highlight the importance of more fundamental research to understand how genes change our brain’s susceptibility to Alzheimer’s disease as we age.”
Professor Jonathan Schott, medical director of Alzheimer’s Research UK, also said the charity is currently funding research projects to try to understand why having the APOE4 gene increases the risk of the disease.
“At this time we do not recommend that people undergo genetic testing for APOE except when participating in research, but this may change in the future,” he added.
The study was published in the journal Nature Medicine.
Around 944,000 people in the UK are thought to be living with dementia, while in the US the figure is around 7 million.
Alzheimer’s affects approximately six in 10 people with dementia.
It is believed to be caused by a buildup of amyloid and tau in the brain, which build up and build up of plaques and tangles that make it difficult for the brain to function properly.
Over time, the brain struggles to cope with this damage and symptoms of dementia develop.
Memory problems, thinking and reasoning difficulties, and language problems are common early symptoms of the condition, which then worsen over time.
Analysis by Alzheimer’s Research UK found that 74,261 people died from dementia in 2022, compared to 69,178 the previous year, making it the leading cause of death in the country.