Sunday, July 21, 2019

CHRFAM7A Gene Explains Why Alzheimer’s Drugs Fail in Humans

Alzheimer’s disease is an irreversible and progressive brain disorder that destroys memory and thinking. This disease eventually effects a person’s ability to complete simple, everyday tasks. Alzheimer’s is currently ranked as the sixth leading cause of death in the United States. Although scientists do not understand what causes Alzheimer’s disease, some believe a genetic mutation may be the cause. 

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According to Medical News Today, Dr. Kinga Szigeti, director of the Alzheimer’s Disease and Memory Disorders Center at the University of Buffalo, found a gene that helped explain why Alzheimer’s drugs appear useful in animals but not in humans. The gene, CHRFAM7A is a fusion gene for alpha-7 nicotinic acetylcholine receptor- a neurotransmitter receptor, acetylcholine, and kinase. Acetylcholine has been linked with the development of Alzheimer’s and plays a crucial role in memory and learning. In Dr. Szigeti’s recent study, she and her team focused on how this CHRFAM7A gene relates to drug effectiveness in humans. 

The study concludes CHRFAM7A is present in two variations, a functional one and one that is not translated into a protein. Even though this gene is specific to humans, only 75% actually have it. Further, three out of four of Alzheimer’s drugs that are available target all of the acetylcholine receptors. Ironically, drugs that specifically target the alpha-7-acetylcholine receptor, have failed in humans. Essentially, an individual's genotype determines what drugs demonstrate to be effective.

"People who don't have the [CHRFAM7A] gene respond better to the drugs available now," Dr. Szigeti reports, "our work confirms that Alpha 7 is a very important target for treating Alzheimer's but the right model — a human model — has to be used when testing new drugs.” In other words, more personalized drugs are necessary for treatment because of the differentiation in humans. A drug may work for 75% of people with Alzheimers, but fail in the remaining 25% or vice versa. 

This article is very interesting but also may raise a lot of concerns that I do not think people are ready to talk about. A few questions that come to my mind would be (a) When is it acceptable to test drugs on people? (b) Would drugs have clinical trials and patients willingly test different methods? (c) How does this affect the pharmaceutical industry and will be personalized drugs become available? Other than human testing, I think this CHRFAM7A gene and its explanation for drugs presents a lot of opportunities for the future of genetics and pharmaceuticals. 

1 comment:

  1. This study really shows how every person can be affected by drugs differently regardless of other factors. Alzheimer's is a terrible disease, and the more information we gather on it the more we are likely to come to some type of cure for this. I like the ending of this, the questions you proposed make one think about the future of medicine in a different sense. "When is it acceptable to test drugs on people?" If people are willing to volunteer for studies like this, I believe they should be allowed to participate. These types of people really open the doors for research.