Despite having a brain full of amyloid plaques, he has been dodging Alzheimer for 30 years: what we know about this rare mutation
It was bad news. When they dug through her DNA, they discovered that she also had a very specific mutation: the E280A mutation in the presenilin 1 gene (PSEN1). People who have this mutation develop the first cognitive problems related to Alzheimer's at age 40 and suffered a rapid deterioration that led to death by the age of 60.
His family tree has been plagued with early-onset Alzheimer's cases for centuries. The "bobera" called him before anyone could find out how bad they were. Today, the 6,000 people who make up this extensive Colombian family have become one of the most important scientific treasures in the study of this dementia.
However, in the case of our patient, the symptoms did not come. What's more, he didn't experience any cognitive decline until he was 70, even though, as the surprised researchers found, his brain had developed most of the important neurological features of the disease. Why wasn't he sick?
One mutation with another green is removed
The study of the patient (whose name has been kept anonymous) was published yesterday in Nature Medicine and explores the possibility that it is another specific mutation that they have found that protects her from the neurological functions of dementia.
According to the researchers, this rare mutation (APOE3 Christchurch - R136S) helps prevent the disease by "blocking the cascade of events that link amyloid with pathology"; a little more technically, it minimizes the binding of apolipoprotein E with heparan sulfate proteoglycans (HSPG). Thus, although he has beta amyloid plaques in the brain, he has not developed the disease.
The result of decades of work by the Colombian neurologist Francisco Lopera, who has studied the family in detail and has accumulated more than 300 brains in the facilities of the University of Antioquia, this discovery is a bombshell. Even if we are finally unable to derive a clinical solution in the medium term.
On the one hand, it helps us to understand much better what the disease that Alois Alzheimer described at the German Psychiatry Congress in 1906 when he told us the story of Auguste Deter is really. On the other hand, it makes us reflect on the use we make of DNA tests today because, far from what it may seem, genetic diagnosis is still a very young science.
And finally, with gene therapies under our arms, it allows us to be optimistic about a disease that today affects more than 30 million people and, we hope, it will triple in the coming years as the world population begins to age. .
Image | Giovanny Ayala