(If you received this blog by email, you might
want to visit the actual site. The pictures work much better there.
Just click on the title “Things great and small.”
As
you likely know, Resonance Women’s Chorus, home to
my major volunteer gig these days, just finished up the season with its
marvelous concert on climate change. After being immersed in this earth-ish topic for months, it’s been fun to find myself
stretched through other layers of reality by a handful of articles I've encountered—outward to this incomprehensibly vast cosmos of ours and inward to
microscopic realms that touch on our very identity. Not trivial matters, but definitely fun.
(Before
I get all wonky, check out these gorgeous roses I
spotted on a walk the other day. If nothing else, they're testimony to two happy facts: it's spring and I'm out walking again. Hooray!)
So,
as a hint of this perspective stretching I mentioned, I offer these few tidbits for your consideration.
First, the microscopic:
The
first set of articles I read had to do with the relatively recent development of a new
technique in the field of genetics. Not long ago, two geneticists developed a technique called CRISPR-Cas9, which
gives scientists the ability to remove and add genetic material at will, altering
an organism's genome—sperm, eggs, embryos—in a way that will be passed on to future
generations. Here’s a video explaining it, if you're curious. The technique has already been used in rats, monkeys, and a few other species.
Folks are pretty certain that it would work in humans. Genetic manipulation
that is limited to non-germ cells (e.g., in GMO foods, gene therapy) already
raises some ethical concerns. But this is about changes that will be
transmitted to subsequent generations. Still unknown are how precise such
changes can be (might I clip too much, insert too little?), how specific (what
if I alter surrounding genes in the process?), and what the side effects might
be (will eliminating, say, a gene that predisposes allergies also damage part
of the natural immune response?).
Aside
from these technical issues, CRISPR raises huge ethical concerns—even theological
ones. It could have great benefits in curing diseases, preventing birth
defects, and so on. But it could also be used in questionable ways, like to
engineer offspring sex, physical characteristics, intelligence, etc. Recently,
a number of people working in the field called for a moratorium on this research in humans until these issues can be addressed. In the words of one scientist, “It
raises the most fundamental of issues about how we are going to view our
humanity in the future and whether we are going to take the dramatic step of
modifying our own germline and in a sense take control of our genetic destiny.” Another comments, “I personally
think we are just not smart enough—and won’t be for a very long time—to feel
comfortable about the consequences of changing heredity, even in a single
individual.”
Yet, just the other day I saw an article about scientists who had attempted to perform this research in human embryos. The experiment failed in most cases—the
embryos died or the DNA was not altered as planned. In other cases, the results were
as feared: in some, the DNA interrupted the process, resulting in some
changed and some unchanged DNA. In other cases, non-target segments of the DNA were
altered, a phenomenon some have called “collateral damage.” So the experiment basically confirmed that the scientists who had issued the warning were right. Still, this research also highlighted the possibility—even the high likelihood—that others
will try again.
The questions this raises are just
mind-boggling. What is identity? What does “I” mean if my DNA, the “building
block” of my distinctive genetic makeup can be altered? And what does it mean
to be a human being if the core features of human existence might be subject to
alteration? If these techniques get perfected, who decides what traits are
worthy of continuing and which are not? It is impossible not to hear the echo of early 20th century programs of eugenics in these questions.
But in a different microscopic domain, another story seems to bring good news: I wrote here before about scientists’
conclusion that viruses make up over 8% of our DNA.
These viruses are evolutionary hitchhikers, organisms that infected our
long-ago ancestors and that gradually became incorporated into our very genes.
Now, that’s mind stretching enough by itself—nearly 1/10 of our DNA consists of
viruses! But even more astounding is what these viruses do for us. In that
earlier post, I noted that they may be responsible for the evolution of the
placenta (the placenta! We’re talking here about the very beginning of our
individual selves). And now, last week, I also learned that some such viruses—endogenous
retroviruses—may “come alive” during the earliest stages of embryonic
development. Retroviruses are not usually our friends—think HIV—but in this
case, these endogenous retroviruses may actually serve to immunize the embryo against other viruses.
Now, this is good news, but it still
challenges any simplistic notions we might hold about ourselves as individual,
self-contained, unitary beings. Just think about it … microscopic viruses—viruses!—stow-aways from pre-human history may be responsible for the placenta that
supported our individual prenatal life and for our immunity to viruses that
might otherwise have done us in. So don't you wonder wonder, where does the “I” in
this process end and the “they” begin?
To leap from the microscopic to the telescopic ...
Two other recent stories escorted me back into my recurrent fascination
with the cosmic. This past week was the 25th anniversary of the launch of the Hubble telescope, which, as you likely know,
has rewritten our understanding of the universe—and illustrated the book. The
Internet was full of Hubble photo gems this week. In case you missed them, I’ll paste in a few, and you can click here for more and here for even more.
Hubble had some struggles from its earliest days (I’m tempted to say it was star crossed, but that seems too easy), with a microscopic flaw in the mirror that caused blurry views of even nearby objects. But with some clever fixes over the years by astronauts turned telescope experts, Hubble has taught us more about the cosmos than we ever knew there was to learn. As you may know from previous posts, I’m a totally amateur but enthusiastic observer of things astrophysical, so I’ve been paying attention to Hubble’s discoveries for years. This anniversary provided a delightful visual memoir of Hubble’s life so far, and I’m hoping for more.
And then, just today, I came across a short
story about another recent Hubble-fueled finding: out there in the universe,
there are “runaway galaxies,” and with Hubble's help, we’re starting to understand them. Scientists
have known for some time about runaway “rogue” planets,
which have either been ejected from their orbits around stars or somehow never
belonged to a star system. They’ve also suggested the existence of runaway
galaxies that are moving so fast they sail free from the “local
cluster” of galaxies whose gravity generally holds galaxies together in a
group. And now Hubble has spotted a runaway galaxy and tracked its trajectory as it veers away from its orbit and heads off into … somewhere. I love that the universe is so unruly.
So, I find this stuff fascinating in its own
right. But this week, with my thoughts shifting from the issue of climate change—which
is global, but local, in the planetary sense—to matters larger and smaller, I realized that both directions of my drift these recent days—the microscopic and cosmic—raise very similar questions: Who
are we? What counts as human if much of our substance is actually other
organisms? Who do we become if we alter the genome that defines who we "naturally" are? Where is our place in a universe whose early beginnings over 13 billion years ago is just now
coming into sight and whose extent, some would argue, is infinite? And that remains stubbornly errant.
If I drift back from the vast, cosmic question to
this smallish, ordinary planet, I wonder at our arrogance to think we matter at
all. If I move the other way, to the microscopic, I wonder if we realize how
tentative and ephemeral our existence is. Either way, I'm struck by the
astonishing improbability of it all. Which cycles me back to earlier musings on this very question, shared here many blogs ago.
I float in these dilemmas for a
while, and then go about my business as if none of these questions mattered, as if they hadn't come to mind. Until they do again.
I wonder what that means.
© Janis
Bohan, 2010-2015. Use of this content is welcome with attribution and a link to
the post.
