By Swara Kalva and Serina Lin
Of all the things that unite us as humans, one would least expect the topic of murder to be on that list. However, as much as we would like to deny it, this fascination with murder is something that seems to pervade our society, from the shows we see on television, to real-life court cases: we are obsessed with murder, and we can’t help it. Now whether this has to do with a commonality in our genes is a topic for another article. Instead, we will be exploring two questions that has long stood the test of time: are we natural-born criminal and to what extent are we able to use genetics to justify our actions?
To settle on an answer, it is important to first consider specific case studies. One such instances is the curious case of Bradley Waldroup. In October 2006, Waldroup got into an argument with his wife and her friend, and ended up shooting the friend 8 times and cutting her open before going after the wife (who fortunately escaped). Waldroup’s children were present at the time of the incident, and as a result, he admitted to the crime. However, in court, his defense team took an unusual approach, and attempted to use genetic evidence to vindicate him. After genetic testing, it was found that Waldroup had a genetic variant on his X chromosome. This gene was one that coded the enzyme monoamine oxidase-A (MAOA). Interestingly enough, many other sociopaths/murderers were found to share the same variant, indicating that this gene could have a significant influence on human behavior. This makes sense, as the MAOA enzyme is responsible for breaking down neurotransmitters, which when built-up, can lead to violence in the person’s behavior.
Many defense attorneys will try to take advantage of using genetic evidence to explain their client’s violent actions in hopes for lighter sentence. In the Bradley Waldroup case, the jurors gave him voluntary manslaughter instead of the death penalty, as the prosecutors asked for, due to his brain scans. Through the brain scans, they were able to detect the MAOA gene. However, this is controversial because according to Dr. Hagerty, everyone’s brain scans are different. For instance, a brain of someone with depression may look different from a brain of someone using drugs. Using these brains scans as evidence may mislead the jurors. Should these serial killers be able to push some of the blame to their genetics?
There seems to be a common thread in the genetics of murderers, but can this be applied to everyone? Unfortunately, there is no definite answer to this- though researchers have found a correlation, a causation between the lack of the enzyme and violent behaviors needs to be found among a large representative sample. Until then, however, there is no need to rush to your nearest geneticist to get tested- so long as you are not currently having sociopathic tendencies, you can go back to happily watching your murder mysteries in peace.