The Violinist's Thumb: And Other Lost Tales of Love, War, and Genius, as Written by Our Genetic Code (33 page)

And yet for all that frailty, a brain with faulty DNA can be miraculously resilient in other circumstances. In the 1980s, a neurologist in England scanned the freakishly large head of a young man referred to him for a checkup. He found little inside the skull case but cerebrospinal fluid (mostly salt water). The young man’s cortex was basically a water balloon, a sac one millimeter thick surrounding a sloshing inner cavity. The scientist guessed the brain weighed perhaps five ounces. The young man also had an IQ of 126 and was an honors mathematics student at his university. Neurologists don’t even pretend to know how these so-called high-functioning hydrocephalics (literally “water-heads”) manage to live normal lives, but a doctor who studied another famous hydrocephalic, a civil servant in France with two children, suspects that if the brain atrophies slowly over time, it’s plastic enough to reallocate important functions before it loses them completely.

Peek—who had a Cuvier-sized noggin himself—had an IQ of 87. It was probably so low because he reveled in minutiae and couldn’t really process intangible ideas. For instance, scientists noticed he couldn’t grasp common proverbs—the leap to the metaphorical was too far. Or when Peek’s father told him to lower his voice once in a restaurant, Peek slid down in his chair, bringing his larynx closer to the ground. (He did seem to grasp that puns are theoretically funny, possibly because they involve a more mathematical substitution of meanings and words. He once responded to a query about Lincoln’s Gettysburg Address by answering, “Will’s house, 227 NW Front St. But he stayed there only one night—he gave the speech the next day.”) Peek struggled with other abstractions as well and was basically helpless domestically, as reliant as a child on his father’s care. But given his other talents, that 87 seems almost criminally unfair and certainly doesn’t capture him.
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Peek died of a heart attack around Christmas in 2009, and
his body was buried. So there will be no Einstein-like afterlife for his remarkable brain. His brain scans still exist, but for now they mostly just taunt us, pointing out gaps in what we know about the sculpting of the human mind—what separated Peek from Einstein, or even what separates everyday human smarts from simian intelligence. Any deep appreciation of human intellect will require understanding the DNA that builds and designs the web of neurons that think our thoughts and capture each “Aha!” But it will also require understanding environmental influences that, like Einstein’s violin lessons, goose our DNA and allow our big brains to fulfill their potential. Einstein was Einstein because of his genes, but not only because of them.

The environment that nurtured Einstein and the rest of us everyday geniuses didn’t arise by accident. Unlike other animals, humans craft and design our immediate environments: we have culture. And while brain-boosting DNA was necessary for creating culture, it didn’t suffice. We had big brains during our scavenger-gatherer days (perhaps bigger brains than now), but achieving sophisticated culture also required the spread of genes to digest cooked food and handle a more sedentary lifestyle. Perhaps above all we needed behavior-related genes: genes to help us tolerate strangers and live docilely under rulers and tolerate monogamous sex, genes that increased our discipline and allowed us to delay gratification and build things on generational timescales. Overall, then, genes shaped what culture we would have, but culture bent back and shaped our DNA, too. And understanding the greatest achievements of culture—art, science, politics—requires understanding how DNA and culture intersect and evolve together.

A
rt, music, poetry, painting—there are no finer expressions of neural brilliance, and just like Einstein’s or Peek’s genius, genetics can illuminate some unexpected aspects of the fine arts. Genetics and visual art even trace a few parallel tracks across the past 150 years. Paul Cézanne and Henri Matisse couldn’t have developed their arrestingly colorful styles if European chemists hadn’t invented vibrant new dyes and pigments in the 1800s. Those dyes and pigments simultaneously allowed scientists to study chromosomes for the first time, because they could finally stain chromosomes a color different from the uniform blah of the rest of the cell. Chromosomes in fact take their name from the Greek for color,
chr
ma,
and some techniques to tint chromosomes—like turning them “Congo red” on shimmering green backgrounds—would have turned Cézanne and Matisse a certain shade with envy. Meanwhile silver staining—a by-product of the new photographic arts—provided the first clean pictures of other cell structures, and photography itself allowed scientists to
study time lapses of dividing cells and see how chromosomes got passed around.

Movements like cubism and Dadaism—not to mention competition from photography—led many artists to abandon realism and experiment with new kinds of art in the early twentieth century. And piggybacking on the insights gained from staining cells, photographer Edward Steichen introduced “bio-art” in the 1930s, with an early foray into genetic engineering. An avid gardener, Steichen began (for obscure reasons) soaking delphinium seeds in his gout medication one spring. This doubled the chromosome number in these purple flowers, and although some seeds produced “stunted, febrile rejects,” others produced Jurassic-sized flora with eight-foot stalks. In 1936 Steichen exhibited five hundred delphiniums at the Museum of Modern Art in New York City and earned mostly rapturous reviews from newspapers in seventeen states: “Giant spikes… brilliant dark blues,” one reviewer wrote, “a plum color never before seen… startlingly black eyes.” The plums and blues may have startled, but Steichen—a nature-worshipping pantheist—echoed Barbara McClintock in insisting that the real art lay in controlling the development of the delphiniums. These views on art alienated some critics, but Steichen insisted, “A thing is beautiful if it fulfills its purpose—if it functions.”

By the 1950s, a preoccupation with form and function eventually pushed artists into abstractionism. Studies of DNA coincidentally tagged along. Watson and Crick spent as many hours as any sculptor ever did creating physical models for their work, crafting various mock-ups of DNA from tin or cardboard. The duo settled on the double helix model partly because its austere beauty bewitched them. Watson once recalled that every time he saw a spiral staircase, he grew more convinced that DNA must look equally elegant. Crick turned to his wife, Odile, an artist, to draw the chic double helix that wound up and down the
margin of their famous first paper on DNA. And later, Crick recalled a drunken Watson ogling their slender, curvy model one night and muttering, “It’s so beautiful, you see, so beautiful.” Crick added: “Of course, it was.”

But like their guesses about the shapes of A, C, G, and T, Watson and Crick’s guess about the overall shape of DNA rested on a somewhat shaky foundation. Based on how fast cells divide, biologists in the 1950s calculated that the double helix would have to unravel at 150 turns per second to keep up, a furious pace. More worrisome, a few mathematicians drew on knot theory to argue that separating the strands of helical DNA—the first step for copying them—was topologically impossible. That’s because two unzipped helix strands cannot be pulled apart laterally—they’re too intertwined, too entangled. So in 1976 a few scientists began promoting a rival “warped-zipper” structure for DNA. Here, instead of one long smooth right-handed helix, right- and left-handed half helixes alternated up and down the length of DNA, which would allow it to pull apart cleanly. To answer the criticisms of double helixes, Watson and Crick occasionally discussed alternative forms of DNA, but they (especially Crick) would almost immediately dismiss them. Crick often gave sound technical reasons for his doubts, but added once, tellingly, “Moreover, the models were ugly.” In the end, the mathematicians proved right: cells cannot simply unwind double helixes. Instead they use special proteins to snip DNA, shake its windings loose, and solder it back together later. However elegant itself, a double helix leads to an awfully awkward method of replication.
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By the 1980s scientists had developed advanced genetic engineering tools, and artists began approaching scientists about collaborating on “genetic art.” Honestly, your tolerance for bullroar has to be pretty high to take some claims for genetic art seriously: pace bioartist George Gessert, do “ornamental plants,
pets, sporting animals, and consciousness-altering drug plants” really constitute “a vast, unacknowledged genetic folk art”? And some perversities—like an albino bunny reconfigured with jellyfish genes that made it glow green—were created, the artist admitted, largely to goad people. But for all the glibness, some genetic art plays the provocateur effectively; like the best science fiction, it confronts our assumptions about science. One famous piece consisted solely of one man’s sperm DNA in a steel frame, a “portrait” that the artist claimed was “the most realist portrait in [London’s National] Portrait Gallery”—because, after all, it revealed the donor’s naked DNA. That might seem harshly reductive; but then again, the portrait’s “subject” had headed the British arm of arguably the most reductionist biological project ever, the Human Genome Project. Artists have also encoded quotes from Genesis about man’s dominion over nature into the A-C-G-T sequence of common bacteria—words that, if the bacteria copy their DNA with high fidelity, could survive millions of years longer than the Bible will. From the ancient Greeks onward, the Pygmalion impulse—the desire to fashion “living” works of art—has driven artists and will only grow stronger as biotechnology advances.

Scientists themselves have even succumbed to the temptation to turn DNA into art. To study how chromosomes wriggle about in three dimensions, scientists have developed ways to “paint” them with fluorescent dyes. And karyotypes—the familiar pictures of twenty-three chromosomes paired up like paper dolls—have been transformed from dull dichromatic images into pictures so flamboyantly incandescent that a fauvist would blush. Scientists have also used DNA itself to build bridges, snowflakes, “nano-flasks,” kitschy smiley faces, Rock ’Em Sock ’Em Robot look-alikes, and Mercator maps of every continent. There are mobile DNA “walkers” that cartwheel along like a Slinky down the stairs, as well as DNA boxes with lids that open,
turned by a DNA “key.” Scientist-artists call these fanciful constructions “DNA origami.”

To create a piece of DNA origami, practitioners might start with a virtual block on a computer screen. But instead of the block being solid, like marble, it consists of tubes stacked together, like a rectangular bundle of drinking straws. To “carve” something—say, a bust of Beethoven—they first digitally chisel at the surface, removing small segments of tubes, until the leftover tubes and tube fragments have the right shape. Next they thread one long strand of
single
-stranded DNA through every tube. (This threading happens virtually, but the computer uses a DNA strand from a real virus.) Eventually the strand weaves back and forth enough to connect every contour of Beethoven’s face and hair. At this point, the sciartists digitally dissolve away the tubes to reveal pure, folded-up DNA, the blueprint for the bust.

To actually build the bust, the sciartists inspect the folded DNA strand. Specifically, they look for short sequences that reside far apart on the unfolded, linear DNA string, but lie close together in the folded configuration. Let’s say they find the sequences AAAA and CCCC right near each other. The key step comes now, when they build a separate snippet of real DNA, TTTTGGGG, whose first half complements one of those four-letter sequences and whose second half complements the other. They build this complement base by base using commercial equipment and chemicals, and mix it with the long, unwound viral DNA. At some point the TTTT of the snippet bumps into the AAAA of the long strand, and they lock together. Amid the molecular jostling, the snippet’s GGGG will eventually meet and lock onto the CCCC, too, “stapling” the long DNA strand together there. If a unique staple exists for every other joint, too, the sculpture basically assembles itself, since each staple will yank faraway parts of the viral DNA into place. In all, it takes a week to design a sculpture and prepare the DNA. Sciartists then
mix the staples and viral DNA, incubate things at 140°F for an hour, and cool it to room temperature over another week. The result: a billion microbusts of Ludwig van.