Is someone born a murderer or do they become one? The argument of nature vs nurture is an age-old one, with no definitive answer in sight. But in 1993, a team of Dutch researchers discovered a gene that they say, makes a man a murderer.
The ‘killer’ gene
Back in 1993, researchers were pouring through a peculiar family tree in the Netherlands, where all the men had a history of violent behaviour. After 15 years of research, they found the men were all missing a certain gene, now known as the ‘killer’ gene.
The gene in question produces an enzyme called M-A-O-A, which is responsible for impulse control. So, if you lack this gene or have it in low-levels, researchers suggest that it makes you pre-disposed to violent acts.
The relevation made headlines in 2009, when an Italian court handed a reduced sentence to a convicted murderer. Genetic tests done on the criminal revealed that the murderer lacked the ‘killer’ gene MAOA. Based on the findings, an Italian judge reduced the original 11 year jail-time to nine years, justifying that the defendant’s genes “make him particularly aggressive in stressful situation”.
It is the environment that matters
Research also shows that the ‘killer’ gene is present in about 30% of men, but in some men the gene is triggered and in others, it remains dormant. A professor at the University of California believes what causes the trigger depends on how happy a childhood one has. Jim Fallon cited his family’s violent history, pointing out that “People with far less dangerous genetics become killers and are psychopaths than what I have. I have almost all of them”.
So why is Fallon not a knife-wielding killer? His explanation is that he had a happy childhood, and the experiences protected him from going down a deadly path.
The implication means that the gene in itself does not make a man a murderer any more than using a kitchen knife makes you a chef. But, under certain environmental conditions, the gene is triggered and influences your behaviour for bad.
So are killers born or bred?
But observers have pointed out the moral questions that a genetic link like that raises. They argue that if criminal behaviour is a result of genes, then would criminals be absolved of their acts, because they were born this way?
Another line of thinking involves eugenics, that if one can genetically remove the gene, perhaps carriers of it could be cleaned out at the womb-stage. But is that not killing a life, as pro-life advocates would argue.
Others too, have warned about breeding a culture of Nazi-type eugenics, where faulty science resulted in mass exterminations.
For now, it appears that a killer is both born and bred.
That is, a genetic pre-disposition to violence, fuelled by an abusive childhood, is a disastrous brew.