Drug addiction isn’t just about making bad choices in life. One study on mutated lab mice is building on a body of work saying genetics and biology can play just an important a role on addiction. The study, conducted by researchers at the University of British Columbia in Vancouver, genetically engineered mice that were capable of resisting cocaine addiction. The results are published in Nature Neuroscience.
It worked by altering the mice’s genes to produce more of a group of proteins called cadherins. The proteins are used in the body like a glue for cells to adhere to each other. But it can also be found on synapsis and are thought to regulate learning and memory.
Cocaine addiction works by creating memories of euphoric highs which the addict seeks to reproduce. So theoretically, injecting more cadherins into someone should cause stronger memory formation and a proclivity toward addiction. But to the researchers’ surprise, the exact opposite happened in these mice. While mice with the genetic mutation were injected with cocaine and given a high, they were half as likely as mice in the control group to seek out more of the drug.
On closer inspection, it turned out the cadherin was working to inhibit a neurochemical receptor in the mice’s brains. This made it harder rather than easier for some neurons to signal each other. So the pleasurable memory of the high didn’t “stick” and the mice behaved neutrally when presented with an opportunity to get high again.
As it relates to people, the finding helps suggest how genetics could play a role in our propensity toward drug addiction. “Addiction is not just bad judgment, but really is more to do with our biology and our biochemistry,” one of the study’s authors, Shernaz Bamji, told NPR.
Our learnings from the study aren’t applicable to humans just yet but it does give us valuable insight into what factors may predispose some people to addiction more than others. And that could ultimately lead to a better understanding of drug addiction and treatment.