Our society seems to love labeling people to help identify them. A case in point is the list of identifiers for sexual orientation that gets longer by the day. Or when psychologists search for why someone behaves the way they do and then labels them with their disorder. For instance, someone becomes psychotic or schizophrenic, bipolar or antisocial.
And so it is with the debate as to whether there is something called the ‘serial killer gene.’ In other words, it's a gene within our DNA that could determine someone’s propensity for violent behavior. If they have it, they get labeled with it.
Dutch geneticist Han Brunner is probably most associated with the concept of a serial killer gene. Through a study he conducted in 1933, he concluded that the low-acting version of monoamine oxidase A, better known as MAOA, was associated with violence in humans. Turns out that MAOA is also known as the “warrior gene,” which is far more romantic but no less potentially violent.
So, what does the MAOA enzyme do? It removes the neurotransmitters (serotonin, epinephrine, norepinephrine, and dopamine) in our body which help to regulate things like mood and the body’s response to stress. Probably important when you think about whether you’re going to kill someone or not. Another gene often listed alongside MAOA is CDH13. According to the Genetic Literacy Project, CDH13 regulates axonal outgrowth (an important development process) and synapse formation. CDH13 has been linked to ADHD, schizophrenia, and bipolar disorder. Again, labels that may or may not have anything to do with whether a person is likely to kill someone.
Unfortunately, this research has been controversial, partly because it’s largely been conducted only on men and there’s been a lack of consistency in the study parameters. Consider a study by a pair of Finnish doctors on a large group of prisoners in Finland. In the study, the researchers concluded that all the offenders carried a low-activity version of the MAOA gene, which they found contributed to the low dopamine turnover rate and could help account for the prisoners' crimes. However, the study didn’t account for alcohol or drug use as part of the person’s crime and focused almost exclusively on ‘impulse’ crimes, excluding pre-meditated crimes. And research shows that while this “warrior gene” can cause aggression in men, it has the opposite effect in women. In fact, a study from the University of South Florida showed that the same low levels of MAOA in women boosted their sense of overall happiness. Who knew?
While researchers have yet to prove there is a single gene that makes someone more likely to commit murder, there are other things that have been proven to contribute. This includes a list of genetic factors associated with criminal behavior such as psychopathy, impulsivity, and the lack of empathy. Environmental factors also have to be added to the list, including childhood trauma and emotional, sexual, or physical abuse. As Anusha Subramanian says in her July 21, 2020, article in the Berkeley Scientific Journal, “…a good way to think about it is that genetics provide an individual with a spectrum and the individual’s environment… determines where you lie on it.” She goes on to say that you might have a predisposition toward violent behavior, but it could lie dormant, potentially forever, until stress factors such as trauma or abuse wake it up.
And so, while there is certainly some common genetic makeup amongst killers, according to Ms. Subramanian, an over-reliance on labeling someone as a carrier of a ‘serial killer gene’ can be problematic. Not only can the label stigmatize the person carrying that gene, possibly leading to an increased risk they might be found guilty of a violent crime they didn’t commit. Conversely, a guilty person identified in this way could be partly absolved of their crimes due to their genetic makeup. And could we go so far as to predict violent behavior?
I was particularly fond of one of the articles I read for this post in which author Emily Tannebaum cited the show Riverdale and how it used (abused) the concept of the serial killer gene in an episode with Betty, one of the lead characters. If you’re unfamiliar with the show, it’s based on the Archie Comic books. The series, however, is a bit dark, and the father of one of the lead characters, Betty, was convicted during the show as a serial killer. As a result, Betty worries endlessly that she may carry the ‘gene.’ If we are to believe the research, though, not only is Betty a female, which means she’s more likely to respond with a smile rather than an aggressive outburst, but she shows an almost annoying amount of empathy as a character with her friends. Perhaps Betty is not the usual candidate for serial killer behavior, although I have to admit, like the show, she has a dark side.
The point here is to be careful in how we label people and how much we believe when watching or reading about fictional crimes. After all, it's fiction. Remember that the next time you watch CSI or NCIS. Take a moment to question how much you believe, especially when the investigators get the DNA results back in ten minutes.
Comments