The Violinist's Thumb: And Other Lost Tales of Love, War, and Genius, as Written by Our Genetic Code (39 page)

What’s more, studying Jewish DNA has helped confirm a once scarcely credible legend among the Lemba tribesmen in Africa. The Lemba had always maintained that they had Jewish
roots—that ages and ages ago, a man named Buba led them out of Israel to southern Africa, where they continue today to spurn pork, circumcise boys, wear yarmulke-like hats, and decorate their homes with emblems of elephants surrounded by six-sided Stars of David. The Buba tale sounded awfully tall to archaeologists, who explained these “Black Hebrews” as a case of cultural transmission, not human emigration. But Lemba DNA ratifies their Jewish roots: 10 percent of Lemba men overall, and half the males in the oldest, most revered families—the priestly caste—have none other than the signature Cohanim Y.

While studying DNA can be helpful in answering some questions, you can’t always tell if a famous someone suffered from a genetic disorder just by testing his or her descendants. That’s because even if scientists find a clean genetic signal for a syndrome, there’s no guarantee the descendants acquired the defective DNA from their celebrated great-great-whatever. That fact, along with the reluctance of most caretakers to disinter ancient bones for testing, leaves many medical historians doing old-fashioned genetic analysis—charting diseases in family trees and piecing together diagnoses from a constellation of symptoms. Perhaps the most intriguing and vexing patient undergoing analysis today is Charles Darwin, because of both the elusive nature of his illness and the possibility that he passed it to his children by marrying a close relative—a potentially heartbreaking example of natural selection in action.

After enrolling in medical school in Edinburgh at age sixteen, Darwin dropped out two years later, when surgery lessons began. In his autobiography Darwin tersely recounted the scenes he endured, but he did describe watching an operation on a sick boy, and you can just imagine the thrashing and screaming in those days before anesthesia. The moment both changed and
presaged Darwin’s life. Changed, because it convinced him to drop out and do something else for a living. Presaged, because the surgery roiled Darwin’s stomach, a premonition of the ill health that dogged him ever after.

His health started to fall apart aboard HMS
Beagle.
Darwin had skipped a prevoyage physical in 1831, convinced he would fail it, and once asea he proved an inveterate landlubber, constantly laid low by seasickness. His stomach could handle only raisins for many meals, and he wrote woeful letters seeking advice from his father, a physician. Darwin did prove himself fit during the
Beagle
’s layovers, taking thirty-mile hikes in South America and collecting loads of samples. But after returning to England in 1836 and marrying, he deteriorated into a honest-to-gosh invalid, a wheezing wreck who often disgusted even himself.

It would take the genius of Akhenaten’s greatest court caricaturist to capture how cramped and queasy and out-of-sorts Darwin usually felt. He suffered from boils, fainting fits, heart flutters, numb fingers, insomnia, migraines, dizziness, eczema, and “fiery spokes and dark clouds” that hovered before his eyes. The strangest symptom was a ringing in his ears, after which—as thunder follows lightning—he’d always pass horrendous gas. But above all, Darwin barfed. He barfed after breakfast, after lunch, after dinner, brunch, teatime—whenever—and kept going until he was dry heaving. In peak form he vomited twenty times an hour, and once vomited twenty-seven days running. Mental exertion invariably made his stomach worse, and even Darwin, the most intellectually fecund biologist ever, could make no sense of this. “What thought has to do with digesting roast beef,” he once sighed, “I cannot say.”

The illness upended Darwin’s whole existence. For healthier air, he retreated to Down House, sixteen miles from London, and his intestinal distress kept him from visiting other people’s
homes, for fear of fouling up their privies. He then invented rambling, unconvincing excuses to forbid friends from calling on him in turn: “I suffer from ill-health of a very peculiar kind,” he wrote to one, “which prevents me from all mental excitement, which is always followed by spasmodic sickness, and I do not think I could stand conversation with you, which to me would be so full of enjoyment.” Not that isolation cured him. Darwin never wrote for more than twenty minutes without stabbing pain somewhere, and he cumulatively missed years of work with various aches. He eventually had a makeshift privy installed behind a half-wall, half-screen in his study, for privacy’s sake—and even grew out his famous beard largely to soothe the eczema always scratching at his face.

That said, Darwin’s sickness did have its advantages. He never had to lecture or teach, and he could let T. H. Huxley, his bulldog, do the dirty work of sparring with Bishop Wilberforce and other opponents while he lay about the house and refined his work. Uninterrupted months at home also let Darwin keep up his correspondence, through which he gathered invaluable evidence of evolution. He dispatched many an unwary naturalist on some ridiculous errand to, say, count pigeon tail feathers, or search for greyhounds with tan spots near their eyes. These requests seem strangely particular, but they revealed intermediate evolutionary forms, and in sum they reassured Darwin that natural selection took place. In one sense, then, being an invalid might have been as important to
On the Origin of Species
as visiting the Galápagos.

Darwin understandably had a harder time seeing the benefits of migraines and dry heaving, and he spent years searching for relief. He swallowed much of the periodic table in various medicinal forms. He dabbled in opium, sucked lemons, and took “prescriptions” of ale. He tried early electroshock therapy—a battery-charged “galvanization belt” that zapped his abdomen.
The most eccentric cure was the “water cure,” administered by a former classmate from medical school. Dr. James Manby Gully had had no serious plans to practice medicine while in school, but the family’s coffee plantation in Jamaica went bust after Jamaican slaves gained their freedom in 1834, and Gully had no choice but to see patients full-time. He opened a resort in Malvern in western England in the 1840s, and it quickly became a trendy Victorian spa; Charles Dickens, Alfred, Lord Tennyson, and Florence Nightingale all took cures there. Darwin decamped to Malvern in 1849 with his family and servants.

The water cure basically consisted of keeping patients as moist as possible at all times. After a 5 a.m. cock-a-doodle-doo, servants wrapped Darwin in wet sheets, then doused him with buckets of cold water. This was followed by a group hike that included plenty of hydration breaks at various wells and mineral springs. Back at their cottages, patients ate biscuits and drank more water, and the completion of breakfast opened up the day to Malvern’s main activity, bathing. Bathing supposedly drew blood away from the inflamed inner organs and toward the skin, providing relief. Between baths, patients might have a refreshing cold water enema, or strap themselves into a wet abdominal compress called a “Neptune Girdle.” Baths often lasted until dinner, which invariably consisted of boiled mutton, fish, and, obviously, some sparkling local H
₂
O. The long day ended with Darwin crashing asleep into a (dry) bed.

Scenes from the popular “water cure” in Victorian times, for patients with stubborn ailments. Charles Darwin underwent a similar regime to cure his own mystery illness, which dogged him most of his adult life. (Courtesy of the National Library of Medicine)

Would that it worked. After four months at this hydrosanitarium, Darwin felt bully, better than at any time since the
Beagle,
able to hike seven miles a day. Back at Down House he continued the cure in a relaxed form, constructing a sweat lodge for use every morning, followed by a polar-bear plunge into a huge cistern (640 gallons) filled with water as cold as 40°F. But as work piled up on Darwin again, the stress got to him, and the
water cure lost its power. He relapsed, and despaired of ever knowing the cause of his frailty.

Modern doctors have scarcely done better. A list of more or less probable retrodiagnoses includes middle-ear damage, pigeon allergies, “smoldering hepatitis,” lupus, narcolepsy, agoraphobia, chronic fatigue syndrome, and an adrenal-gland tumor. (That last one might explain Darwin’s Kennedy-esque bronze glow late in life, despite being a hitherto pasty Englishman who spent most hours indoors.) One reasonably convincing diagnosis is Chagas’ disease, which causes flu-like symptoms. Darwin might have picked it up from the South American “kissing bug,” since he kept a kissing bug as a pet on the
Beagle.
(He delighted at how it sucked blood from his finger, puffing up like a tick.) But Chagas’ disease doesn’t fit all Darwin’s symptoms. And it’s possible that Chagas merely crippled Darwin’s digestive tract and left him vulnerable to deeper, dormant genetic flaws. Indeed, other semiplausible diagnoses, like “cyclical vomiting syndrome” and severe lactose intolerance,
^*
have strong genetic components. In addition, much of Darwin’s family was sickly growing up, and his mother, Susannah, died of undetermined abdominal trouble when Darwin was eight.

These genetic concerns become all the more poignant because of what happened to Darwin’s children. Roughly 10 percent of leisure-class Victorians married blood relatives, and Darwin did his part by marrying Emma Wedgwood, his first cousin. (They shared a grandfather in Josiah Wedgwood, the crockery maven.) Of the ten Darwin children, most were sickly. Three proved infertile as adults, and three died young, roughly double the child mortality rate in England. One, Charles Waring, survived nineteen months; Mary Eleanor lived twenty-three days. When his favorite child, Anne Elizabeth, fell ill, Darwin took her to Dr. Gully for the water cure. When she died anyway, at age ten, it snuffed the last lingering remnant of Darwin’s religious faith.

Despite any bitterness toward God, Darwin mostly blamed himself for his children’s infirmity. While most children born to first cousins are healthy (well north of 90 percent), they do have higher risks for birth defects and medical problems, and the numbers can creep higher still in unlucky families. Darwin stood uneasily ahead of his time in suspecting this danger. He tested the effects of inbreeding in plants, for instance, not only to shore up his theories of heredity and natural selection but also to see if he could shed light on his own family’s ailments. Darwin meanwhile petitioned Parliament to include a question about consanguineous marriages and health in the 1871 census. When the petition failed, the idea continued to fester, and Darwin’s surviving children inherited his anxieties. One son, George, argued for outlawing cousin marriages in England, and his (childless) son Leonard presided over the First International Congress of Eugenics in 1912, a congress devoted, ironically enough, to breeding fitter human beings.