Morning Edition has a strange story today about the exploration of one neuroscientist of his own family’s history, specifically its psychological and neurological quirks. To not put too fine a point on it, the scientist in question finds out that he has a history of violence in his family, and, that he carries a genetic variant implicated in violent behavior under particular conditions, as well as telling neurological patterns found among psychopaths. Here’s the relevant section:
After learning his violent family history, he examined the images and compared them with the brains of psychopaths. His wife’s scan was normal. His mother: normal. His siblings: normal. His children: normal.
“And I took a look at my own PET scan and saw something disturbing that I did not talk about,” he says.
What he didn’t want to reveal was that his orbital cortex looks inactive.
“If you look at the PET scan, I look just like one of those killers.”
Fallon cautions that this is a young field. Scientists are just beginning to study this area of the brain — much less the brains of criminals. Still, he says the evidence is accumulating that some people’s brains predispose them toward violence and that psychopathic tendencies may be passed down from one generation to another.
The Three Ingredients
And that brings us to the next part of Jim Fallon’s family experiment. Along with brain scans, Fallon also tested each family member’s DNA for genes that are associated with violence. He looked at 12 genes related to aggression and violence and zeroed in on the MAO-A gene (monoamine oxidase A). This gene, which has been the target of considerable research, is also known as the “warrior gene” because it regulates serotonin in the brain. Serotonin affects your mood — think Prozac — and many scientists believe that if you have a certain version of the warrior gene, your brain won’t respond to the calming effects of serotonin.
Fallon calls up another slide on his computer. It has a list of family members’ names, and next to them, the results of the genotyping. Everyone in his family has the low-aggression variant of the MAO-A gene, except for one person.
“You see that? I’m 100 percent. I have the pattern, the risky pattern,” he says, then pauses. “In a sense, I’m a born killer.”
Fallon is being a bit dramatic for effect obviously, but as I said to Eric Michael Johnson this is like finding out you have a history of alcoholism in the family, as well as a genetic variant which results in the less efficient metabolization of alcohol. You know what you know, and you know what you have to do to not put yourself in a position where your predispositions could mix with a dangerous set of choices.
Going back to this example and being more practical, what if behavior genomics and neuroscience advance to the point where you can find out the odds of your child having issues with impulse control, heightened aggression, and reduced independent ethical judgement (e.g., guilt as opposed to shame) are all greater than than expectation. All things being equal the research is telling you that instead of having a 0.1% chance of landing in jail for violent crime, your offspring has a 5% chance. There are all sorts of things you might do, and choices you might make. If, for example, you yourself know that guilt is just something you aren’t heavily gifted with, and that gets you intro trouble in the long term (as you make a sequence of ‘rational’ unethical choices on a regular basis), you might choose a profession which is very transparent so that you don’t have to make ethical decisions on a regular basis where short term self-interest is in conflict with long term self-interest & socialized conceptions of right & wrong. Go into finance if you can do math. Become a lawyer if you can’t.
Razib Khan’s degrees are in biochemistry and biology. He has blogged about genetics since 2002, previously worked in software development, is an Unz Foundation Junior Fellow and lives in the western US. He loves habaneros.
June 29th, 2010 at 5:37 am
[...] This post was mentioned on Twitter by GraceBarkwell, razib khan and Ron Simon, World Amazing Things. World Amazing Things said: Your genes are just the odds | Gene Expression: Morning Edition has a strange story today about the exploration o… http://bit.ly/bCoNBt [...]
June 29th, 2010 at 7:01 am
[...] living horror?Well, that’s just what happened to a neuroscientist named Jim Fallon. According to a report in Discover magazine, based on an episode of Morning Edition, Fallon was doing research on his families [...]
June 29th, 2010 at 10:21 am
Yes, drugs which raise seroton, like Prozac, can cause violence.
The Physicians Desk Reference states that SSRI antidepressants and all antidepressants can cause mania, psychosis, abnormal thinking, paranoia, hostility, etc. These side effects can also appear during withdrawal. Also, these adverse reactions are not listed as Rare but are listed as either Frequent or Infrequent.
Go to http://www.SSRIstories.com where there are over 3,900 cases, with the full media article available, involving bizarre murders, suicides, school shootings/incidents [55 of these] and murder-suicides – all of which involve SSRI antidepressants like Prozac, Zoloft, Paxil, etc, . The media article usually tells which SSRI antidepressant the perpetrator was taking or had been using.
June 29th, 2010 at 12:08 pm
I think one would totally want everyone to know if one had psychopathic killer neurology.
cf. “Mad Dog Tim” in “The Life and Times of Tim”, http://www.vureel.com/video/15186/The-Life-and-Times-of-Tim-S01E04 .
June 29th, 2010 at 3:18 pm
Razib, you got any good info or links about how changes in gene expression in *neurons* effect this type of scenario? i was intrigued by Kandel’s explanation about how learning is actually a change in the protein production in neurons and i was wondering how this relates to behavior and why it is (apparently) weaker in effect than inherited genes and the inherited epigenome. I.e. Say this person from the NPR article was a clone of one of his parents so he had a much greater chance of being a killer. How powerful of a change in neuronal gene expression would we need to overcome this tendency and is this even possible? In short: Is this why, once you’re an adult, it’s basically impossible to change your personality in any significant way? Thanks
June 30th, 2010 at 12:42 pm
True, the genes are the odds, especially for behaviors… but for things like some diseases, the odds are pretty much 100%. It seems like making and understanding those kinds of distinctions would be where genetic counseling comes in. And, of course, careful presentation in the media.
This also kind of relates to a discussion of genetic testing that’s going on over at PRI’s The World Science, if anybody wants to come over and check out some very different public-radio stories on genetics. Mayana Zatz, a Brazilian geneticist and genetic counselor, is online there til July 13 taking questions and comments.
http://www.world-science.org/forum/genetic-testing-personal-genomics-ethics-mayana-zatz/
June 30th, 2010 at 3:38 pm
[...] Morning Edition on National Public Radio has an interview with a neuroscientist “uncovering a dark secret.” Someone at Discover magazine has been blogging about it. [...]
June 30th, 2010 at 5:18 pm
[...] Razib says what can’t be said too often: Your genes are just the odds [...]
July 7th, 2010 at 8:39 am
[...] Razib says what can’t be said too often: Your genes are just the odds [...]