Discovery of a gene related to brain aging
Knowing our DNA can help us to prevent and treat neurodegenerative diseases.
Aging is an essential process in the cycle of life.. Generally speaking, aging affects cells, and more specifically, their genetic content.
Of course, this process does not evolve randomly; in fact, not only do we age more or less depending on how we eat and the general lifestyle we lead, but there are also genes that regulate our physical and psychological maturation. In fact, an important discovery has recently been made in this regard: a gene has been found that is related to the way in which we age. a gene related to the way in which our brain ages has been found, which is interesting for many reasons.This is interesting for many reasons that we will now see.
DNA and the maturation of our mind
At the ends of the double helix strand that forms our DNA (enclosed in every cell of our body) are a series of sequences of nucleic acids known as telomeres. nucleic acids that are known as telomeres.. Each time a cell divides, these ends are shortened, and when it reaches a certain limit, it causes cell death. Cell loss is part of aging, which leads to a decrease in the body's activities.
One of the organs most sensitive to the passage of time is undoubtedly the brain.. The loss of neurons takes its toll, and there is a long list of problems that this causes, such as lack of motor coordination or dementia.
In research, there has always been a special interest in studying the aging of the brain, for example to reveal its relationship with neurodegenerative diseases such as Parkinson's or Alzheimer's disease. Not long ago, one of these investigations located a gene that is related to this process.
A gene that affects the frontal lobe
Scientists at Columbia University (United States), Asa Abeliovich and Herve Rhinn, examined about 1900 samples of healthy brains. From their observations they were able to conclude that a gene, called TMEM106Bplays a key role in how human brains age.
It appears that certain strains of this gene cause the frontal lobe to age at a faster rate than in other people. This is important because this region is involved in executive functions, such as decision making, managing our focus of attention or planning. Frontal lobe aging causes a decrease in these vital functions and increases the risk of the appearance of diseases known as neurodegenerative.
Genes as risk factors
Finding genes that explain the appearance of Biological abnormalities is nothing new. One example is the ApoE gene, responsible for the transcription of the Apolipoprotein E protein, which in one of its variants (specifically ApoE4) is associated with an increased risk of suffering from neurodegenerative disease. associated with an increased risk of Alzheimer's disease..
The novelty of this discovery is to have found a gene that controls the life rhythm of a region of the brain. As the discoverers themselves argue, aging is the main risk factor for neurodegenerative diseases and this research may help to predict the onset of these diseases or even to intervene in them through so-called gene therapies.
How does this gene for brain aging act?
For this study, Asa Abeliovich and Herve Rhinn first obtained genetic data from 1904 autopsy samples of brains that had not suffered from any neurodegenerative disease. Once obtained, they compared them with average data from brains of the same age, looking specifically at 100 genes whose expression increases or decreases with age. The result is that one gene causes differential aging, the so-called TMEM106B.
The concept of differential age is simple; it is nothing more than a difference between the biological age of the organ (in this case the brain), with the chronological age of the organism. The frontal lobe turns out to be older or younger than what corresponds to the age of the person taking as a reference his or her day of birth.
According to its discoverers, the TMEM106B gene begins to show its effect from the age of 65 years, and works to reduce the stress caused by aging on the brain. on the brain. As far as we have seen, there are different alleles, i.e. variants of the gene. Some protect against this stress (its normal function), while others do not perform this task, causing the process of brain aging to accelerate.
Linked to a disease
In their study, these researchers also found that a variant of the gene progranulin has an effect on aging, but not as prominent as TMEM106B. Although they are two different genes and are located on different chromosomes, both act on the same signaling pathway and are associated with the development of a neurodegenerative disease known as frontotemporal dementia. a neurodegenerative disease known as frontotemporal dementia..
This clinical syndrome is characterized by frontal lobe degeneration, which may extend to the temporal lobe. In adults aged 45 to 65 years, it is the second most common form of dementia after early-onset Alzheimer's disease, affecting 15 out of every 100,000 people. In people over 65, it is the fourth most common type of dementia.
However, the study was conducted from the perspective of healthy brains, so further studies are needed to confirm certain points with their links to disease. But, as Abeliovich pointed out, aging makes people more vulnerable to neurodegenerative diseases and vice versa, diseases cause accelerated aging.
(Updated at Apr 12 / 2024)