Thankfully
How You Live Your Life Matters

 

According to scientific orthodoxy, all living things were entirely determined by their genetic code. Hence the neo-Darwinian dogma: DNA is destiny. But the latest news is that DNA is not destiny. As a recent article in Discover Magazine makes clear, the science of epigenetics has some humbling news for predestinarian scientists of genetics. Neither human beings nor any other animal is reducible to the nucleotide sequence in DNA. Instead, who we are is also determined by how we are.

 
November 22, 2006  
Dear Concerned Citizen,
by Dr. Benjamin Wiker
 

The name of the science, epigenetics, puts genetics in its place. Genetics is the study of genes, the so-called basic units of heredity encoded in specific sequences of DNA nucleotides.  Epigenetics means the study of those things over and above the gene (“epi” is a Greek prefix that means “above” or “over”).

For too long, scientists have assumed that there isn’t anything “above” the gene.  That is, anything that appeared to be above the gene—the cell, and more importantly, the larger multi-celled organism and everything it is, does, and ever will do—they declared to be reducible to the gene.

Hence, the wild fervor in, and jubilation about, the Human Genome Project.  If we map the entire genome—the entire genetic sequence—then human nature will be an open book. Having cracked the code, we’ll be able to read our form and fate.

Such was the doctrine of necessity, but “it ain’t necessarily so.” According to science writer Ethan Watters, the recent work of epigeneticists “has made it increasingly clear that for all the popular attention devoted to genome-sequencing projects, the epigenome is just as critical as DNA to the healthy development of organisms.”

Proof? Here’s an interesting example. We’ve been led to think that every malady we suffer—say, obesity, or proneness to diabetes or cancer—is caused by our having an unlucky gene. And even worse, we’ll pass this unlucky gene to our offspring, and they will do the same in turn.

Enter a neat little experiment with Agouti Mice, so named because they carry a particular gene, mellifluously called the agouti gene, that not only disposes them to being overweight but also to contract diabetes and cancer. A sure case of DNA is destiny.

Not so. Instead of trying to micromanage the genome, researchers did the motherly thing, and changed the mouse’s diet. Whereas before, most of the offspring of such mice were doomed to display the same traits, now, after a diet change, the majority of the offspring produced were perfectly healthy mice.

DNA is not destiny. The “diet rich in methyl donors,” a type of molecule found in many ordinary foods, such as onions, garlic, and beets, turned off the agouti gene in the offspring.  The lesson: there is a big difference between having a gene, and having that gene expressed.

But things are stranger still. Let’s turn from mice to rats. As with human mothers, so also with mother rats: some are very motherly, others are cold and distant.  Researchers found that affectionate mother rats actually had a positive effect on their offspring after they were born.

The nurturing activity (licking their young) actually caused the hippocampus in the brain of offspring to develop more fully and to release less of a particular stress hormone, cortisol. The result: calmer, less skittish rats. The rats with cold and distant mothers, by contrast, were nervous and timid, and developed smaller hippocampi.

Why? The mother’s motherly licking released serotonin in her little pups’ brains, which nudges the hippocampus to send a protein message to turn on genes that inhibit stress.  A little motherly love, and DNA is no longer destiny.

From mice (and rats) to men? What does it mean?

To begin with, this crack in reductionism cannot help but become bigger and bigger. If mere diet changes and a little motherly love can have such dramatic effects, what else might change our DNA expression from a pre-written script, to a story we help write, both for ourselves and our offspring?

Epigenetics therefore represents a major shift…back to common sense. Predestinarian DNA-ism denies the common sense notion that what we choose to do and not to do has a real effect on our lives and the lives of others. But if such small changes makes such large differences in mice and rats, what we human beings choose to do and not to do could make a world of difference. Free will is not only real; to a yet undetermined extent, it can override DNA.

But these latest scientific discoveries also spell the end of the reductionist paradigm of neo-Darwinism. As with Darwinism, neo-Darwinism wanted to keep everything simple. The chant that DNA is destiny was a way to make life, including human life, so simple that it needed no other explanation than that provided by brute materialism.

Neo-Darwinians therefore claimed that they could explain all of human life in all its complexity in terms of genes—bodies, minds, romance, art, literature, passions, pursuits, politics, religion, music. All could be put down to which genes won out in the struggle for survival, and some occasional happy mutations.

Now it seems like the reverse. The greatest effect on our genes might be epigenetic.  Beautiful music, deep romance, and great art could yield just as significantly beneficial results as motherly and fatherly affection. Suddenly, epigenetically caused gene expression is as much if not more important than the genes themselves.

This presents a serious difficulty to neo-Darwinism. The charm of neo-Darwinism was that it was simplicity itself.  All complexity could be explained by a simple, one-way mechanism. Beneficial genes caused beneficial traits; natural selection picked off the less fit; those with more beneficial traits survived to hand on their genes.

But epigenetics opens up the possibility that there are literally countless things above the level of the gene that could contribute to something’s ability to survive, be it mouse or man. That is not simplicity itself, for the genes only tell half the story. The other half is epigenetic.


The Most Fundamental Discovery of this New Science: We are Wired to Connect

Neuroscience has discovered that our brain’s very design makes it sociable, inexorably drawn into an intimate brain-to-brain linkup whenever we engage with another person. That neural bridge lets us impact the brain—and so the body—of everyone we interact with, just as they do us.

Even our most routine encounters act as regulators in the brain, priming emotions in us, some desirable, others not. The more strongly connected we are with someone emotionally, the greater the mutual force. The most potent exchanges occur with those people with whom we spend the greatest amount of time day in and day out, year after year—particularly those we care about the most.

During these neural linkups, our brains engage in an emotional tango, a dance of feelings. Our social interactions operate as modulators, something like interpersonal thermostats that continually reset key aspects of our brain function as they orchestrate our emotions.

The resulting feelings have far-reaching consequences, in turn rippling throughout our body, sending out cascades of hormones that regulate biological systems from our heart to immune cells. Perhaps most astonishing, science now tracks connections between the most stressful relationships and the very operation of specific genes that regulate the immune system.

To a surprising extent, then, our relationships mold not just our experience, but our biology. The brain-to-brain link allows our strongest relationships to shape us in ways as benign as whether we laugh at the same jokes or as profound as which genes are (or are not) activated in t-cells, the immune system’s foot soldiers in the constant battle against invading bacteria and viruses.

That represents a double-edged sword: nourishing relationships have a beneficial impact on our health, while toxic ones can act like slow poison in our bodies.

Virtually all the major scientific discoveries I draw on in this volume have emerged since Emotional Intelligence appeared in 1995, and they continue to surface at a quickening pace. I intend this book to be a companion volume to Emotional Intelligence, exploring the same terrain of human life from a different vantage point, one that allows a wider swath of understanding of our personal world.

When I wrote Emotional Intelligence, my focus was on a crucial set of human capacities within an individual, the ability to manage our own emotions and our inner potential for positive relationships. Here the picture enlarges beyond a one-person psychology—those capacities an individual has within—to a two-person psychology: what transpires as we connect.

Take, for example, empathy, the sensing of another person’s feelings that allows rapport. Empathy is an individual ability, one that resides inside the person. But rapport only arises between people, as a property that emerges from their interaction. Here the spotlight shifts to those ephemeral moments that emerge as we interact. These take on deep consequence as we realize how, through their sum total, we create one another.


"We have been the recipients of the choicest bounties of heaven. We have been preserved, the many years, in peace and prosperity. We have grown in numbers, wealth and power, as no other nation has ever grown. But we have forgotten God.

We have forgotten the gracious hand which preserved us in peace and multiplied and enriched and strengthened us; and we have vainly imagined, in the deceitfulness of our hearts, that all these blessings were produced by some superior wisdom and virtue of our own. Intoxicated with unbroken success, we have become too self-sufficient to feel the necessity of redeeming and preserving grace, too proud to pray to God that made us!" - Amen

Abraham Lincoln's Proclamation of 1863


Seventh Generation

The chiefs of the Six Nations of the Iroquois Confederacy were obliged by their constitution's Great Law of Peace to consider the impact of their decisions on the seventh generation to come. This notion is foundational to some aspects of modern day "green economics."


Epigenetics: Genome, Meet Your Environment

As the evidence accumulates for epigenetics, researchers reacquire a taste for Lamarckism.

"The environmental lability of epigenetic inheritance may not necessarily bring to mind Lamarckian images of giraffes stretching their necks to reach the treetops (and then giving birth to progeny with similarly stretched necks), but it does give researchers reason to reconsider long-refuted notions about the inheritance of acquired characteristics. Eighteenth-century French naturalist Jean Baptiste de Lamarck proposed that environmental cues could cause phenotypic changes transmittable to offspring. 'He had basically good idea but a bad example,' says Rohl Oflsson, Uppsala University, Sweden."

The Scientist


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  Dinesh D'Souza
Dinesh D'Souza, the Rishwain Research Scholar at the Hoover Institution at Stanford University, served as senior domestic policy analyst in the White House in 1987-1988. He is the best-selling author of Illiberal Education, The End of Racism, Ronald Reagan, The Virtue of Prosperity, and What's So Great About America. D'Souza's forthcoming book The Enemy at Home will be published by Doubleday in January 2007.

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