Is there a "murder gene"?
Plus when people are tone-deaf, COP26, COVID in deer, brainless sponges, carbon-making microbes, and science used to justify horrible acts.
Hello! How are you?
There’s a lot going globally right now. Of course, there’s much information on the recently concluded climate conference- COP26 that ended in Glasgow to digest. I would say that this episode of The Climate Question is probably the best immediate analysis of what happened at COP26.
Meanwhile, over a million children between the age of 5 and 11 have been vaccinated in the United States after a week of vaccines being available to that age group. To add to a bit of positive news, the new antivirals from Merck and Pfizer might be a late gamechanger in the treatment of COVID-19.
These are important stories. But there are also other stories that I’ve been following this week.
Deer COVID
I live in a neighborhood where there are many trees. Quite often, I get to see white-tailed deer when I’m go for a walk.
The alarming news is that a large number of these deer have been infected with SARS-CoV-2, the coronavirus that causes COVID-19. These deer were likely initially infected by deer-hunters. Now there is deer to deer transmission. Another animal that is infected opens up the possibility of the virus spreading and further mutating.
And now, for other news.
Is there a gene that pushes some men to murder?
This is the focus of my most recent column in Hindustan Times.
You may think it’s a silly question. After all, everyone is responsible for their own actions, right? And the short answer is “no”.
But that has not prevented experts from going on the stand and claiming that genes predispose people to violence. Or in other words that some people can’t help being violent. In all, a dozen or so cases— including one that moved from court to court in the US for nearly a decade— have hinged on the use of this argument. But what does the science say?
This question isn’t just relevant only to a few cases, but open up a broader discussion at the leading-edge of behavioral genetics and society: to what extent can you blame your genes for bad behaviour (leading up to murder)? What about intelligence? Impulsivity? Empathy?
Do people actually have free will? Or do genes-environment interactions make people do what they do? The arguments in the field of behavioral genetics are contentious. The bleeding edge of genetics is fraught with scary consequences for society.
But first, the case.
In 2012, a man in the American state of New Mexico was charged with choking and beating to death a relative of his girlfriend. They both then poured cooking oil over the body and burned it. The defense for the suspect wanted to argue that a gene variant, as well as mistreatment as a child led him to his violent behaviour.
The man pleaded guilty. He did not say that he didn’t commit the crime. He tried to argue that his genes made him do it. The distinction of premeditation was the crux of the legal defense. Premeditation is important because it can lead to a lighter sentence.
Actually, this argument goes back a few decades. Here’s the landmark study in Science in 1993 that found the gene variant that was linked to aggression. This became known later as the “murder gene” or the “warrior gene”.
But finding that someone has a variant of these gene has no predictive value. Just because someone has it doesn’t mean they will murder someone. This is what I’ve pointed out in the column as well.
As a science, genetics has advanced from the era of Mendel and his observations on pea plants. Most health-related traits (and this is particularly true of behaviours) don’t result from one change in a gene causing a single trait. There may be hundreds or thousands of genes acting in tandem with each individually contributing less than 1% to the observable outcome. In the past few decades, we have also learned that non-gene sequences of DNA and environmental factors change how genes work. That’s why we haven’t found a single genetic factor for heart disease, obesity, or depression, though we know that heredity plays a role.
In short, there is no gene that acts as a switch for criminal behaviour. Social conditions, emotional state, and lifestyle can also nudge someone to make a choice at a particular moment. That is why criminal investigations also search for motive, means, and opportunity.
I don’t think this is the last word on genetic determinism. Our genetics can act as constraints on how we act, but we are responsible for our actions within those constraints.
Language isn’t just words.
This week, I learned about a women who broke down in front of a researcher explaining just how her relationship with her partner had ended. Her partner said that she never understood when he was making sarcastic remarks. And this was true. She didn't.
A researcher found that like 1% of the population, the woman had amusia. She couldn't recognize musical tones.
Tone is a critical part of music and language. If you play a song like "Happy Birthday", most people with amusia recognize the song from the words. If you play a wordless version on the piano, they don't. A lot of people say they are tone-deaf, but only a subset of them have amusia.
What else I’ve read.
Where is gene therapy going? This is quite an engaging read.
A comet (that broke into three or more pieces as it entered the atmosphere) may have fused desert sand into glass when it explodes around 12,000 years ago in the Atacama Desert. Such an event today in a highly populous area of the world would be catastrophic.
Deep sea microbes make a graphite-like material. This is the first evidence of biologically-produced elemental carbon. Very cool stuff.
Climate change is messing up the direction that some birds migrate.
Brainless sponges have the ability to share information. And the cool thing is this information-sharing process predates our nervous systems by hundreds of millions of years.
Killing whales has left an enormous hole in the ocean ecosystem.
What I’ve been listening to.
12 million slaves. The largest forced migration in human history. One of the most amazing podcast interviews I’ve heard this year focuses on slavery, and how science was used to justify horrid acts through history. It’s a wonderful podcast, and I ended up buying the book the author has just published.
In a few weeks, I’ll post my favorite popular science books of 2021.
Stay well.
Anirban