It’s in Our DNA

Genesis 2:4-8

In the day that the Lord God made the earth and the heavens, when no plant of the field was yet in the earth and no herb of the field had yet sprung up—for the Lord God had not caused it to rain upon the earth, and there was no one to till the ground; but a stream would rise from the earth, and water the whole face of the ground— then the Lord God formed man from the dust of the ground, and breathed into his nostrils the breath of life; and the man became a living being. And the Lord God planted a garden in Eden, in the east; and there he put the man whom he had formed.

Psalm 139:13-18

For it was you who formed my innermost parts;
    you knit me together in my mother’s womb.
I praise you, for I am fearfully and wonderfully made.
    Your works are wonderful - 
  that I know very well.

My frame was not hidden from you,
  when I was being put together in a secret place,
    when I was being intricately woven in the depths of the earth.
Your eyes beheld my unformed body;
    all the days that were formed for me were written down
  before any one of them had happened.

How incomprehensible your thoughts are to me, O God!
    How vast is the sum of them!
I can’t even count them—they would outnumber the grains of sand;
    If I would come to the very end—I would still be with you.

* * * * *

When I was in college 100 years ago, I majored in Biology. I liked math and science and was fairly good at it – with the exception of organic chemistry – although I have to admit that I never really understood physics. But I loved Biology. I loved learning about life. 

When I went to seminary I felt I was also learning about life, just from a different angle. They weren’t contradictory, they were complementary. The analogy I use is that it’s like lenses: you can look at the universe through a microscope or a telescope and it’s still the same universe, but what you see is vastly different. I have always thought of religion and science as simply being different lenses through which to see life. 

Which is a way of saying you should be warned: last week I threw out words like apocalyptic, eschatology and dispensationalism. Today it’s epigenetics. Because I am unabashedly geeky that way, and I am blessed to serve a congregation that puts up with stuff like that, and rolls with it. So thank you. 

My two favorite classes in college were Embryology and Genetics. I was fascinated by how life formed; how does a single cell become a complex organism? If that single cell replicates with exactly the same genetic code – the same DNA – which it does – then how does its daughter cells know to become part of a heart, or a toe, or your brain? How do they become different, in just the right place, at just the right time? It’s called cell differentiation – but how does it work? 

Well, it’s a pretty fascinating process, beginning with a ball of cells that really all act just the same, and then they start flattening out so there’s a front and a back and a top and a bottom, and then they do this really cool fold so you get three different types of cells – the endoderm, the ectoderm and the mesoderm– one layer becomes your guts and organs, one becomes your skin, brain and nerves, and one becomes your bones and muscles and blood cells. And it just perks right along from there. As if it is baked right in, for all those cells to know what they’re supposed to do. Incredible. 

Oddly enough, I learned something about that process recently when I was reading The Book of Joy – which is an interview with the Dalai Lama and Archbishop Desmond Tutu. They were talking about the role of stress and suffering in a person’s development and growth. Archbishop Tutu was making the case that “nothing beautiful in the end comes without a measure of some pain, some frustration, some suffering. This is the nature of things. This is how our universe has been made up.”

Then the author, Douglas Abrams, includes almost a side-note about biological process in fetal development. He writes, 

I was amazed to hear from prenatal researcher Pathik Wadhwa that there is indeed a kind of biological law at work in these situations. Stress and opposition turn out to be exactly what initiate our development in utero. Our stem cells do not differentiate and become us if there is not enough biological stress to encourage them to do so. Without stress and opposition, complex life like ours would never have developed. We would never have come into being. 

Stress and opposition are necessary to life. Yes, they can be destructive. But sometimes, they are life-giving. Sometimes, they are absolutely necessary. We would not be who we are without them, but undeveloped creatures without form. 

We are “fearfully and wonderfully made,” the Psalmist writes. And the more we learn, the more amazing it is. 

One of the more sobering things I learned in embryology is that things can go wrong every step of the way. That’s how our professor taught the course: if this doesn’t happen, then that congenital defect is what you’ll see. I even learned that identical twins are the result of development gone wrong. Who knew? It has something to do with this coating called the zona pellucida falling off that little ball of cells too early, and instead of one little ball of cells, you have two. I have to admit it gave me pause to think if it weren’t for that ‘mistake,’ I would not have been. 

I came away from that class astounded that anyone ever comes into this world whole and intact.

But people do. All the time. And so do cats and dogs and fleas and ticks and elephants and amoebas. It’s incredible. 

What’s even more incredible is how resilient we are once we get here. And how powerful that resilience really is. Because that resilience is baked in, too.  

But to explain this, I need to give you a little more geeky stuff about DNA and cells. (You’re such good sports.)

Sometimes DNA is turned on once and for all, and it stays that way.  Say, for instance, that the genetic code is turned on so that a particular cell becomes part of your heart. Once that happens, it will always, always, always be a heart cell. It will never wake up one day and say, “Gee, I think I’d rather be an elbow.” Thank goodness it doesn’t have a choice, right? Some DNA is permanently, irreversibly on. And that’s a good thing. 

But other DNA is turned on for just a little while, like the light goes on in your car when you open the door, and then goes off again. So when you eat something, your gut cells get ready and turn on and do what they need to do and then go back to sleep. It’s situational and temporary. And that’s a really good thing, too.

And some DNA is dormant until something happens, like age, and then it’s turned on and never goes off again. Like gray hair. This isn’t going away. I don’t know; maybe that’s good, too. 

But some DNA in our cells is turned on because the environment changes, and it needs to be ‘on’ for the organism to survive. That’s where epigenetics comes in. This wasn’t even a ‘thing’ when I was in college. Back then scientists knew there was a whole lot of DNA that didn’t seem to be doing anything, so naturally they called it “Junk DNA”. Because based on what they knew, it seemed useless. But it turns out it’s just waiting there, because who knows? Someday we might need it. Maybe it is kind of like a junk drawer that way. You keep it around, because hey, it might be useful. (At least that’s what I keep telling myself.)

So “junk DNA” turns out to be like that. When the time comes, our bodies know how to find that item we need and get it out and use it. 

I heard a lecture at Denison last year about epigenetics, and the professor told us about an experiment using  yeast cells. They’re simple, one-celled organisms, they replicate really fast, and they’re all the same – all exactly the same DNA – so you can compare one against the other easily. 

They exposed the yeast to ultraviolet light, which kills most yeast. But some of the yeast survived. The DNA hadn’t changed at all – it was still the same DNA in the cells that lived and the ones that died - but some of the yeast turned on a piece of DNA that kept it from dying. The stress flipped a trigger so different genes were expressed, genes that allowed it to survive. 

Isn’t that amazing? 

But what’s even more amazing is that those surviving cells passed on the trigger to the next generation. And the next and the next. So that all the subsequent generations lived, too. They passed on their ability to survive the new circumstances.

Do you see what I’m trying to say? Resilience is built right into us. Baked into us. Code that can be turned on at just exactly the right time. And the even more amazing part is that we can pass that resilience down to our children. That switch that turns on at just the right time? We pass that down, too. We don’t just pass down the potential for resilience, we pass down resilience itself.  

We are fearfully and wonderfully made, the Psalmist writes. And the more I learn, the more I am astounded. Just astounded. 

So. End of lesson. Thank you for looking through a different lens this morning at this miraculous, wondrous gift of life. And so as not to leave you with one lens, I offer you one of my favorite poems to close with – with an invitation to look at your own life with fresh appreciation. 

The Summer Day, by Mary Oliver
Who made the world?
Who made the swan, and the black bear?
Who made the grasshopper?
This grasshopper, I mean-
the one who has flung herself out of the grass,
the one who is eating sugar out of my hand,
who is moving her jaws back and forth instead of up and down-
who is gazing around with her enormous and complicated eyes.
Now she lifts her pale forearms and thoroughly washes her face.
Now she snaps her wings open, and floats away.
I don’t know exactly what a prayer is.
I do know how to pay attention, how to fall down
into the grass, how to kneel down in the grass,
how to be idle and blessed, how to stroll through the fields,
which is what I have been doing all day.
Tell me, what else should I have done?
Doesn’t everything die at last, and too soon?
Tell me, what is it you plan to do
with your one wild and precious life?

Rev. Karen Chakoian
First Presbyterian Church
Granville, Ohio