Tuesday, March 17, 2015

The Human Genome--Science Takes a Giant Step

About 15 years ago, science crashed through a wall and found itself in a new world of exciting and terrible possibilities. The Human Genome Project officially announced it had “decoded” the human genome. Since 2000, genomic scientists have learned to deduce such interesting facts as:
·         what part of Africa your slave ancestors were abducted from;
·         how many children are the result of Mom cheating on Dad; (5 percent) 
·         when humans left Africa and settled the rest of the earth.
·         And, are some men part Neanderthal?

The “human genome,” just as a reminder, is all of the combinations of amino acids that make up the DNA of the human species.

DNA and RNA carry your physical traits, mixed and matched from your parents and ancestors. They tell each of your cells what it’s for and how to do what it does. The genetic code is composed of just 4 amino acids, repeated in a mind-boggling variety of sequences and rhythms, stuck end to end in pairs to form those double helixes. And—most mind-boggling of all—the same genetic code is at work in all living things: You can insert firefly genes into a plant and the plant will glow in the dark.

The Genome Project has confirmed what the Good Book told us all along, children. All humans are related. We didn’t coincidentally develop in a couple of areas of the globe. Asians, Blacks, Caucasians, Native Americans and Australian Aborigines all originated from the same tired old Black woman in Africa. We are all brothers and sisters. We are all, in some sense, from Ethiopia. Now more than ever, race is an intellectual and historical construct. It’s a consequence of genes pooling in geographical backwaters, a childhood phase of the human species that we may outgrow if we overcome geographical boundaries.

And the Genome Project has delved even further into our species's history. It turns out that chimpanzees and bonobos, our closest relatives, have 99 percent of the same genes as us. So, I thought, it should be no surprise that the expressions of almost anyone you despise can be compared so successfully with those of Curious George the cartoon primate.

But that leaves the interesting question, what’s the 1 percent difference?

First, to put that 99 percent in perspective, the Human Genome Project also discovered that humans have 75 percent of the same genes as—pumpkins. Gives you a new respect for jack-o-lanterns, doesn’t it? It has been many, many years since any of us has photosynthesized. But, when you find yourself staring toward the only light in the room, or digging your bare toes into dark soil, spare a thought for our pumpkin sisters.

The question of what makes humans different from other animals has occupied the minds of scientists for centuries—that is, when they took time off from looking for a cure for impotence. And once again, those scientists have come up with the same answer: there’s damn little separating us from the beasts. Once it was believed that only humans used tools, but since then we have found evidence of several non-humans using tools. Then it was thought that perhaps speech was the defining human characteristic, until some woman went and taught chimpanzees and gorillas to speak sign language. (Not to mention the Scottish terrier I had who routinely stood by the back door and said "Ou'" pronouncing it without the final T, like all good Scots—and knew very well what it meant, too.) We know the difference is not raw intelligence. Tests on whales and dolphins prove they’re nearly as smart as we are, and the tests they’ve administered on us prove vice-versa.

So how can we define our difference? Is it in our ability to build cities? But then there’s coral, essentially a great city in which the inhabitants have learned to recycle their own bodily waste to create semi-precious homes. Our understanding of mathematics? Recent research shows that bees navigate long distances by advanced calculus. And speaking of navigation, whales navigate the length and breadth of the oceans, we know not how. One theory is that they use astronomy.

It is not, as science once proposed, that we alone have a moral sense. Frankly, most of our dogs have as strong a moral sense as we have.

But we are different, aren’t we? We tell stories. We are, as author Karen Armstrong puts it, “meaning-seeking creatures that fall easily into despair.” We ask a lot of questions. We slaughter other species and even each other in huge numbers, and brag about it, and feel shame about it.

Science’s latest unsatisfying answer from the Human Genome project tells us that we are quite simply another mutation off the primate branch of the evolutionary tree. Of the 99 percent of genes we have in common with chimps, different genes are switched on or off.  For instance, the gene that makes head hair stop growing is switched on in chimps and off in us.

In our brains, the main difference is a sugar molecule on our cerebral cortex. We are mutant, dome-top, switched-on cousins of the chimps. In common with captive monkeys, we have minds that never quit. We are incessantly pulling the cabinet knobs and pressing the toilet lever looking for something interesting to happen. But supercharged as we are, our toilet levers and knobs are urban renewal, contour plowing, corporate book-jiggering, and nuclear weapons.

The truth may be that what makes us different from them is precisely the fact that we are obsessed with what makes us different from them. We are like chimps that have smoked weed, and now see and hear ourselves from a slight distance. “You can think if you think you can.”

The Human Genome Project may radically change how we see ourselves. For so many thousands of years, Westerners have read that God gave us dominion over the other animals. The Human Genome Project could draw us closer to our own extended family. We might work harder to learn the languages and viewpoints of our cousins the primates.

I hope that understanding the amazing thing that is the genetic code will give us more respect for the genome itself, make us less likely to keep goobering it up with plastics waste, nuclear weapons tests, and gene-altering “medicines.”

It might help us sort out some of the tough nature-versus-nurture questions we have grappled with for centuries. Are we weird because of the traumas of our youth, or did we inherit our weirdness from our parents?

If it’s good for anything, our newborn ignorance in the face of the Human Genome Project will remind people that—with any luck—we are maybe somewhere near the beginning of the march of evolution, along with the rest of the beasts and plants. It doesn’t go ape-Australopithecus-homo habilis-homo erectus-us! We are still hairy-knuckled, stick-wielding, impulse-driven ape creatures, who have only recently glimpsed our reflections in the murky surface of the gene pool and heard our thoughts coming back to us through the haze.


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