For many people, fear of flying or of spiders skittering across the lounge room floor is more than just a momentary increase in heart rate and a pair of sweaty palms.
It’s a hard-core phobia that can lead to crippling anxiety, but an international team of researchers, including neuroscientists from The University of Queensland’s Queensland Brain Institute (QBI), may have found a way to silence the gene that feeds this fear.
QBI senior research fellow Dr Timothy Bredy said the team had shed new light on the processes involved in loosening the grip of fear-related memories, particularly those implicated in conditions such as phobia and post-traumatic stress disorder.
Dr Bredy said they had discovered a novel mechanism of gene regulation associated with fear extinction, an inhibitory learning process thought to be critical for controlling fear when the response was no longer required.
“Rather than being static, the way genes function is incredibly dynamic and can be altered by our daily life experiences, with emotionally relevant events having a pronounced impact,” Dr Bredy said.
He said that by understanding the fundamental relationship between the way in which DNA functions without a change in the underlying sequence, future targets for therapeutic intervention in fear-related anxiety disorders could be developed.
“This may be achieved through the selective enhancement of memory for fear extinction by targeting genes that are subject to this novel mode of epigenetic regulation,” he said.
Mr Xiang Li, a PhD candidate and the study’s lead author, said fear extinction was a clear example of rapid behavioural adaptation, and that impairments in this process were critically involved in the development of fear-related anxiety disorders.
“What is most exciting is that we have revealed an epigenetic state that appears to be quite specific for fear extinction,” Mr Li said.
Dr Bredy said this was the first comprehensive analysis of how fear extinction was influenced by modifying DNA.
“It highlights the adaptive significance of experience-dependent changes in the chromatin landscape in the adult brain,” he said.
The collaborative research is being done by a team from QBI, the University of California, Irvine, and Harvard University. The study was published this month in the Proceedings of the National Academy of Sciences of the United States of America.
The researchers miss the boat, in my opinion, in how they explain in interviews that their research should try to be carried over to humans. What I understand from the interviews is that the researchers are focused on targeting human genes with some outside action.
Recommending human gene therapy smells like an agenda. If these epigenetic modifications were induced by training in rodents, wouldn’t the next step be research into reversal training or therapeutic activity for humans?
The researchers also found: “Importantly, these effects were specific to extinction training and did not occur in mice that had been fear conditioned, followed by a single reactivation trial, therefore arguing against the possibility that such epigenetic modifications are nonspecifically induced by the retrieval or reconsolidation of the original fear memory.”
This is fine for rodent studies where the origins of both the disease and the cure are all exerted externally. I don’t see that it necessarily applies to humans.
After all, we’re not lab rats. We can perform effective therapy that doesn’t involve some outside action being done to us.
http://surfaceyourrealself.com/2015/02/22/if-rodent-training-has-beneficial-epigenetic-effects-how-can-the-next-step-be-human-gene-therapy-surfaceyourrealself/
@14003024: So your hypothesis is that fear is positively linked to reproduction?
Well, I’m not getting laid anyways. However, my crippling apiphobia does prevent me from deriving any enjoyment in the outdoors. (Nevermind that this discourages outdoors exposure, which reduces opportunities for finding mates, and additionally discourages a healthy lifestyle which affects mating appeal).
So, I would be interested in following this research and seeing if it leads to any treatments for strong phobias. If it does, future people like me might have an improved quality of life, and improved odds of reproduction!
My hypothesis is that tampering with genes is a dangerous practice when not perfected. I’m sorry to hear about your phobia, but what might cure your phobia can lead to mutations in others.A good scientist should be willing to take others’ opinions into consideration.Before you dismiss my opinion think objectively about what I am saying and don’t let your personal phobia cloud your judgement on this subject.
Fear is a chain reaction in the brain that starts with a stressful stimulus and ends with the release of chemicals that cause a racing heart, fast breathing and energized muscles, among other things, also known as the fight-or-flight response. The stimulus could be a spider, a knife at your throat, an auditorium full of people waiting for you to speak or the sudden thud of your front door against the door frame.
Fear is controlled by a particular gene which can be extinguished through modification of DNA or by controlling a novel mechanism of gene regulation associated with fear extinction.
Fear is the natural way in which our bodies avoid possible dangerous situations.Fear comes from negative experiences.In an attempt to avoid these experiences from reoccurring our body ‘remembers’ the factors which lead to this experience and triggers our body’s fight or flight response,controlled by the hypothalamus,when they are present.This induces an emotional state referred to as fear and allows our bodies to react much faster.If we get a fright our sympathetic nervous system as well as our adrenal-cortical system are activated.Nerves are hereby triggered and hormones are released into the bloodstream.The way our bodies react to fear physically enables us to handle a threat.By modifying our genes to control fear we run the risk of losing our ability to trigger our fight or flight response.The fear of rejection will possibly also be lost.This fear illustrates our psychological and emotional need for companionship and without this need,or the fear of being rejected,we would have a decrease in the reproduction of our species.