The gene in question for this study was a2d3 or straightjacket, which is a unique sensory gene because its pathway is in the brain, instead of being in the peripheral nerves, which is usually the "norm" for pain sensory genes. To test this gene they inserted the genetic sequence into fruit flies and exposed the flies to an excessive heat wave, those who were under the influence of the gene failed to move away from the heat. To test where the gene was being affected (brain or peripheral nervous system) they had to isolate the gene, induce pain then observe activity in the mouse, which they observed in the brain. Mapping of other genetic pathways allowed the researchers to conclude it was indeed a2d3 that had the brain pathway. Why we should care is this gene is found in the flies, mice as well as in humans and the mutant of gene a2d3 causes synesthesia which is where one sense triggers the others (including pain). Research on this gene may allow the development of a pain reliever that would be able to counteract the brain pathway and intercept the pain signal.