The human brain is enormously complex, no one can deny that, but some parts of our brains are similar to those of some simpler animals. Think of it this way: a motorcycle may not have a car’s rear differential, air conditioning, or safety features, but they do both have an engine. Some of the same engine problems might exist between a car and a motorcycle, the same way some of the same problems exist between an animal’s brain and part of our own.
This is the case with us, zebrafish, and what researchers call the “social gene.”
Like us, zebrafish are social animals, preferring to swim in schools just like we prefer to go out and hang with our friends. EGR1 is a gene that humans and zebrafish both have which is responsible for social behavior. Researchers at the University of Oregon believe that a mutated EGR1 alters social behavior and may even be a big cause behind conditions like autism.
The team tested this theory by putting zebrafish in an aquarium with a transparent partition that blocked any smell or sensations from movement in the water. Normally, zebrafish swim toward each other on sight, even with the partition. When they saw another zebrafish through the partition, those with a normal EGR1 swam toward their fellow fish, but those with mutated EGR1 genes did not.
Applying fish behavior to humans
This doesn’t mean that a mutated EGR1 gene is all there is to autism and other mental health conditions, such as schizophrenia and depression. Changes in the EGR1 gene can mean changes in the gene that makes tyrosine hydroxylase, a chemical that the body needs to make dopamine. What this research does is fill in one very important part of the puzzle and enable researchers to figure out more from there.
“This is giving a small piece of the brain circuits involved in social behavior,” says Philip Washbourne, a biology professor at the University of Oregon. “From there, we can go upstream and downstream and try to put the circuit together.”
Looking at the changes in the zebrafish with mutated EGR1 genes, though, the researchers were able to attribute this change to their less social behavior. We share certain similarities between our brains and some other species’ brains. Observations like these help medical and neurological researchers identify correlations in simpler organisms’ brains, like zebrafish or mice, and then look for similar causes in humans, bringing us one critical step closer to treating certain diseases.
Source Study: Around the O — A ‘social’ gene in fish could contain new clues to autism | Around the O (uoregon.edu)