Tuesday, November 18, 2008

The Ghosts Inside Your Genes

Spinal Tap
Originally uploaded by Seeking Tao
For years I pulled my own existence out of emptiness.
Then one swoop, one swing of the arm, that work is over…

Do you think I know what I am doing?
That for one breath or half-breath I belong to myself?
As much as a pen knows what it is writing,
or a ball can guess where it’s going next.
Rumi, as quoted by Suzanne Segal, in Collision with the Infinite.

Today’s title comes from the subtitle of a lecture I went to yesterday on epigenetics.
The speaker, Dr. Michael Skinner (here he is on the BBC) opened by saying,
“My grandmother’s environment will cause me disease as an adult.”

This is not biology as usual and I have written about epigenetics before.
What Dr. Skinner pointed out was that the current paradigm for the genetic basis of disease does not explain well established observations:

1) There are regional differences in diseases. In Japan, for instance, there’s a lot of stomach trouble, but cardiovascular systems are strong. The reverse is true for the U.S.
2) There is a relatively low frequency of genetic diseases. E.g., only about 5% of breast cancers have the BRAC 1 and 2 genes. 95% of breast cancers are caused by something else.
3) Identical twins have different frequencies of disease.
4) Many environmental toxins don’t mutate the DNA, but they do cause disease.

Skinner’s list went on, but you get the point I hope.
We do inherit diseases tendencies, but that is not the entire story.
Diseases don’t always arise because a healthy gene mutates.
And yet, the environment is clearly doing something to our genes.

If a mother is exposed to an environmental toxin, her offspring can be affected in an “non-Mendelian” manner.
Usually, an inherited trait diminishes in frequency with each new generation.
But, Skinner spoke of finding 90% of off-springs affected even in the fourth generation- so we’re talking here about a great-great grandmother as if she was just yesterday.

My daughter was birthed in a darkened room, so she wouldn’t be shocked by bright lights, into a large basin filled with warm water to ease the transition…

How can one describe a baby being born to no one?
She had no mother, yet the birth occurred just fine, and in the years to come the mothering function would take care of her…

she was an extraordinary child who showed no signs of being traumatized in any way… I was able to “fool” everyone into thinking I was just as I used to be…. How extraordinary the mind thought. There is no one here, and it’s apparently unnecessary to be someone for mothering to take place.

Mothering mothers, just as talking talks and thinking thinks.
The mind has a hard time getting used to this.
Suzanne Segal, Collision with the Infinite, on the birth of her daughter, Arielle.

We are all conditioned to have expectations, both in life and in science.
Buddhists call it conditioning. Scientists speak of paradigms.
Something’s got to give in our preconceptions for progress to occur.

Dr. Skinner is working with “endocrine disruptors,” molecules that bind to hormone receptors, molecules like phthalates. They are in shampoo, that new car smell, plastic bottles, the fungicides for fruits including those for wine.

What he’s found is that exposing a mother to these poisons, or rather, exposing her embryos (for we’re talking rats here) led to a huge array of adult onset diseases.

The genes themselves are not changed in the sense of being mutated.
Rather, the DNA in the embryos is being methylated in new patterns.
The new pattern of methylation turns some genes on that usually would be off, while other genes, usually on, are forever silenced.
In the past when I’ve heard of this it was called imprinting.

We have such potential within our cells. We begin life truly “totipotent.”
Development and growth requires turning off most of that potential.
We need to differentiate into tooth and claw and hair to become our human selves.
We get a double dose of most chromosomes, one paternal one maternal.
Often that’s too much. Imprinting can silence genes and whole swaths of chromosomes.

But, that full potential still resides inside us.
And while some environmental inputs to our mother’s womb cause hyper- and hypo- methylation that drive us to disease, there’s no reason a priori that these shifts must all be detrimental.
Some changes may be beneficial. And they definitely impinge on evolution.
Dr. Skinner is licking his chops on that angle and I am intrigued myself.

To Arielle, who was born into the infinite…

She was a delightful, happy child who was constantly impressing people with her precociousness. She was able to laugh in the face of any challenge…
I was relieved to see her so happy, since I had repeatedly wondered whether …the radical shift of consciousness that had accompanied the last five months of my pregnancy had left any problematic impressions on her.

Whatever impressions may have been left did not appear to have traumatized her. As she has matured into a teenager, she has continued to exude the wise happiness that has always radiated from her… In fact, she has frequently expressed a clear knowing that she is both different from and the same as other people.

At times she finds this confusing, and generally she would rather not speak about it. But on at least one occasion she has said, “You know, Mom, when people look at you and they think you’re someone, but you know you’re not that person?”

“Yes, sweetheart,” I’ve answered, “I do know that experience.”
Suzanne Segal

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