Alzheimer’s Disease – New Genes Tied to Alzheimer’s Disease

What are the causes of Alzheimer’s?

Even though a lot of research has been done in this field, the exact cause of Alzheimer’s hasn’t been found yet. But basically what happens is that brain protein fails to function in the normal way which disrupts the usual way brain cells work and then causes their death which triggers a series of toxic events.

Research has shown that Alzheimer’s disease is mostly caused by a combination of genetic, lifestyle and environmental factors which affect the brain over time. Even though the genetic cause has been mentioned here, less than 1% of the time, Alzheimer’s is caused due by the presence of a specific genetic change that virtually guarantees that the bearer will develop this disease.

This rare presence of genetic change will cause a person to develop this disease even before they are old. The onset of the disease mainly affects that region of the brain that controls the memory but the process usually begins many years before the first symptom is noticed. The loss of neurons over time slowly spreads to other parts of the brain.

The pattern of the damage caused to the neurons is quite predictable. During the later stages, it has been seen that the brain has shrunk comparatively.

Mainly two brain proteins play a key role when it comes to analyzing the onset of Alzheimer’s. The first is called Plaques. The main constituent of this is beta-amyloid which is a fragment of a larger protein. When these fragments cluster together, they tend to have a toxic effect on the neurons which disrupt the communication between the cells.

The second one called Tangles is formed of tau proteins which play a role in supporting the neuron’s internal and transporting the nutrients and other essential materials.

If someone suffers from Alzheimer’s, their tau protein will change shape and organize itself into structures which are then called Neurofibrillary tangles that disrupt the aforementioned transport system and is toxic to the cells.

New Genes Linked to Alzheimer’s Disease:

Chunshui Yu and Mulin Jun, researchers at the Tianjin Medical University have led a research team that has discovered two new genes which are potentially linked to Alzheimer’s. They identified the genes by exploring which genes are turned on and off in the hippocampus of the people who are suffering from this disease. Their research regarding this was published in PLOS Genetics.

The hippocampus is that part of the brain which controls the brain is one of the first regions in the brain that falls under the grip of this disease. To find out which genes are most affected by this disease, the researchers first identified the genes that expressed higher or lower levels in the hippocampus of the people who suffer from Alzheimer’s and compared that to those of healthy brain.

After they conducted the research, they found out that 24 Alzheimer’s-related genes appeared to have an effect through the hippocampus by using previous genomic and hippocampus gene expression data. Some of the genes had also appeared at other tests which usually were concerned with finding the genes that contribute to this disease.

Some were also involved in the biological process that is related to the disease itself, such as plaque information and cell death. The two unknown genes are called PTPN9 and PCDHA4.

The research team further validated their findings by comparing the expressions of the genes to that of two dozen other genes by comparing them to images of individuals’ brains. The brain shrinkage caused by Alzheimer’s can be measured through medical imaging. By doing this, the researchers established that the expression of two of the genes is related to the size of the hippocampus and is concerned with a diagnosis of Alzheimer’s disease.