New gene triples risk for Alzheimer's disease

Alzheimer's disease is just one of the few types of dementia, but it is the most prevalent.  A new gene variant was discovered that not only increases the chances of Alzheimer's disease, but triples it!  It is approximated that less than one percent of people have this gene variant, which also has an unhealthy effect on memory and thinking in the elderly who do not have dementia.  TREM2 is responsible for working with the immune system to reduce brain swelling and get rid of dementia's telltale sign of "sticky deposits."  When mutated, the gene no longer functions efficiently enough to take care of the inflammations and sticky deposits.  The fact that scientists now know about TREM2 could help bring about a new way to reverse the mutation or develop a treatment for its harmful effects.

Aside from TREM2, the only gene known to correlate to Alzheimer's is ApoE.  Even though only about seventeen percent of all people have the variant form of this gene that leads to Alzheimer's, the affected gene accounts for about half the people who have been diagnosed.  Studies of the variant TREM2 gene show similar results to those corresponding to the variant ApoE gene.  Of the people examined for the research who were over 85, those who had the variant TREM2 without Alzheimer's showed findings of decreased cognition.  Not only does the variant correlate to cognition, but it has a role in assisting the immune system as well.

 

Alzheimer's is always a scary possibility when thinking about aging in the future.  Although I always knew it had to do with the loss of memory and some motor skills, I never knew exactly what the disease entailed.  All the damage takes place in the brain, with the buildup of amyloid plaques and neurofibrillary tangles, in addition to loss of nerve cell connections and death of these neurons.  What I am still somewhat confused about is whether or not anyone in the world can develop Alzheimer's disease.  Are the variant TREM2 and ApoE genes already in a person's DNA at birth (since some cases of the disease are considered to be inherited throughout a family), or can the genes change to become the variants as a person ages?  As for the discovery of TREM2 and the gene's functions, I think it would be a great breakthrough for scientists to research this new information further in order to develop a treatment for the currently incurable disease.