I consider this article a severe and harmful distortion of science. Its author, Kathleen Miles, is a senior editor of PuffHo World without any apparent biological training. And it shows: she swallows the tasteless pablum dished out by Tanzi and Chopra without a grimace, or a word of criticism. Let’s deconstruct this ludicrous article, which, mercifully, is short. (It also has two videos.)
Physician and best-selling author Deepak Chopra has an empowering message: You can actually modify your own genes through your actions and behaviors. “We are literally metabolizing something as ephemeral as experience or even meaning,” Chopra said in an interview this week at the Milken Institute Global Conference in Beverly Hills, California. “If somebody says to me, ‘I love you,’ and I’m in love with them, I suddenly feel great, and I make things like oxytocin and dopamine, serotonin, opiates. And if someone says to me, ‘I love you,’ and I’m really thinking they’re manipulating me, I don’t make the same thing. I make cortisol and adrenaline.”
Throughout the piece one sees the conflation of two things: changes in gene expression versus changes in the structure of the genes themselves. Certainly when your body has a physiological reaction, or there’s neuronal activity, genes are involved, either having made the hormones or neurotransmitters that are expressed, or becoming activated to make more of them. Genes are also involved in rewiring your brain in light of your experience. But this is all differential activation of genes that remain themselves structurally unchanged. Their sequences don’t change: they’re just turned on and off.
This has been known for years, but Tanzi and Chopra deliberately (or so I think) confuse gene expression (as in the second paragraph above) with gene structure, as in the paragraphs below:
If certain experiences happen enough times, they can affect how genes are expressed and packaged without altering DNA, said Harvard Medical School professor Rudy Tanzi. This phenomenon, called epigenetics, is gaining increasing popularity among scientists. “Every experience will cause chemical changes in your body and in your brain, and those chemical changes will then cause genetic changes,” said Tanzi, who recently co-authored the book Super Brain with Chopra. “If those genetic changes occur often enough and with persistence, that can lead to modification of those genes such that they react the same way in the future because they’ve been trained.” Though not a typical outcome, there have been reports of such modifications being passed onto subsequent generations, in what’s known as transgenerational epigenetic evolution.
Now epigenetics is not the differential expression of unchanged genes, but the structural alteration of genes (which itself can change their expression) by modification of their DNA sequence—usually by attaching methyl groups (one carbon and three hydrogen atoms) onto specific DNA bases. Epigenetic modification of genes has also been known for a while, can affect their expression, and can be adaptive, as when male and female genes are differently methylated, and expressed, in the egg that results from fertilization. But all the adaptive changes in methylation we know of are themselves coded in the DNA; that is, the DNA has a sequence that tells other parts of the DNA to become epigenetically modified in an adaptive way.
This is not what people like Tanzi and Chopra mean by “epigenetics,” though. They mean that the changes in DNA come not from the DNA code itself, but from the environment, and then become inherited. Indeed, such “Lamarckian” changes in DNA modification can occur from the environment, and be inherited—but not for more than a few generations. It is not a stable form of inheritance, and hence can’t play a role in evolution, or (as the duo repeatedly implies) in changing the genes of your children. Such modifications have never, to my knowledge, been the basis of a biological adaptation, because they disappear within a few generations. All evolutionary adaptations that I know of have, when investigated finely, proved to rest on changes in the sequence of DNA bases. None of them have been shown to rest on environmentally-induced epigenetic modification of the DNA.
I suspect that by “conservative evolutionary biologists,” Tanzi (who’s threatened me with action for libel) means me, and perhaps Dawkins and others who have called Tanzi and Chopra out for their exaggerations. After all, we’re the annoying fleas on the body of quackery, demanding evidence for their claims. The problem with the mouse example is that , like all epigenetic modifications
And here’s the telling admission by Tanzi (my emphasis):
While scientists have found evidence for epigenetic changes that are passed down in mice and water fleas, Tanzi noted that there is only circumstantial evidence for the phenomenon occurring in humans. Still, he emphasized that the connection between our actions and our genes is clear. “The brain is not static. It’s dynamic. It’s changing all the time,” Tanzi said. “And you’re in charge of how it changes.”
So—no evidence in humans. Nevertheless, the Quack Train has left the station, and nothing will induce these two to provide proper caveats about the research, for they’re selling books and CD’s about how we can change our genes by changing our behavior. I don’t mind these people speculating about what might happen in humans in the absence of any evidence, but I consider it unethical to use those unfounded speculations to sell stuff to a gullible public.
Note, in the above, Tanzi’s argument that the brain is “dynamic” and “changing all the time.” Well of course it does: it changes every time we receive sensory information, have a thought, or feel an emotion. So what? That says absolutely nothing about modifying our genes. And it’s a bit misleading to say “you’re in charge of how it changes.” As a determinist, I don’t think we are (what does Tanzi mean by “you,” anyway?). Even if you’re not a determinist, you must admit that changes in your brain often have nothing to do with your volition. If you’re permanently traumatized by some horrible event, or your memories are altered by external events, that occurs without your conscious will.
To see how far these guys take this stuff, here are two videos from the PuffHo piece, described as follows:
Deepak Chopra, physician and best-selling author, and Rudy Tanzi, Harvard Medical School professor, spoke with Kathleen Miles, senior editor of The WorldPost, at the Milken Institute Global Conference in Beverly Hills, California on April 28, 2014.
They’re short, so listen up. There’s more quackery here than in a duck colony!
Note Chopra’s statement: “There is no experience of any kind that doesn’t get metabolized into gene regulation and neuroplasticity.” Metabolized? What does he mean? If he means that experiences affect the expression of genes we already have, then fine. And if he means that our brains get “rewired” from experiences, that’s true, too. But then Tanzi chimes in at 1:45 and says that these chemical changes in the brain cause genetic changes that can be passed on. That’s simply distorting the truth; we have no idea that that can happen in our species (or stably in any species), and considerable evidence against it.
Now it’s possible that these guys could be right to some extent—that is, there may be a few permanently inherited modifications of our genes induced by epigenetic alterations stemming from the environment. But I’d bet a lot of money that we don’t find, say, five of them that are adaptive within the next decade.
3. This is science journalism at its very worst. Miles has not taken the slightest effort to vet Tanzi and Chopra’s claims by consulting other scientists. She is gullible and just wants to sell a big story. PuffHo should be ashamed of itself for publishing stuff like this, but, as we know, that rag has no shame. Their job is to sell website clicks, and if they have to push quackery to do it, so be it. Frankly, this is far worse than sideboob!
More quackery from Twitter, with Deepakity trying to get us “atheist Darwinists” to pay attention: