What Is Your DNA Worth?

dnamap

Your DNA may be up for sale. And the sale depends on an exaggerated picture of genetic power and destiny.

“Success in sight: The eyes have it!” Thus the scientific journal Gene Therapy greeted the news, in 2008, that an experimental treatment was restoring vision to 12 people born with a congenital disorder that slowly left them blind. Healthy genes were injected to replace the faulty mutations in the patients’ retinas, allowing an 8-year-old to ride a bike for the first time. A mother finally saw her child play softball. Every patient, the researchers reported, showed “sustained improvement.” Five years in, a book declared this “breakthrough” — a good-gene-for-bad-gene swap long pursued as a silver bullet for genetic conditions — as The Forever Fix. 

Earlier this month, two of the three research teams running these trials quietly reported that the therapy’s benefit had peaked after three years and then begun to fade. The third trial says its patients continue to improve. But in the other two, all the patients tracked for five years or more were again losing their sight.

Not all gene therapy ends in Greek-caliber tragedy. But these trials serve as a sadly apt parable for the current state of human genetics. This goes especially for the big-data branch of human genetics called Big Genomics. In five years of talking to geneticists, biologists, and historians, I’ve found that the field is too often distinguished by the arc shown here: alluring hope, celebratory hype, dark disappointment.

We live in an age of hype. But the overselling of the Age of Genomics — the hype about the hope, the silence about the disappointments — gobbles up funding that we might spend better elsewhere, warps the expectations of patients and the incentives of scientists, and has implications even for people who pay genetics scant attention. Many hospitals, for instance, are now collecting genetic information from patients that they may market to “research partners” such as drug companies. Some take more care than others do to secure informed consent. (Had blood drawn lately? Read everything you signed that day?) It’s not just that they’re selling you this stuff. They may well be selling you. And the sale depends on an exaggerated picture of genetic power and destiny.

To be sure, medical genetics has chalked up some sweet victories. Our growing ability to spot rare mutations, for instance, is helping doctors diagnose and sometimes treat nasty rare diseases. Last fall, for instance, doctors in Kansas City, Missouri sequenced an infant dying of liver failure, saw that he had inherited a rare mutation that both his parents happenefd to pass to him, devised a way to counter the mutation’s disruption of his immune system, and saved his life.

But when it comes to how genes shape the traits and diseases that matter most to us — from intelligence and temperament to cancer and depression — genetic research overpromises and underdelivers on actionable knowledge. After 110 years of genetics, and 15 years after the $3.8 billion Human Genome Project promised fast cures, after more billions spent and endless hype about results just around the corner, we have few cures. And we basically know diddly-squat.

I know — diddly-squat is rough talk. Yet this is hardly a radical claim. Geneticists and doctors outside of Big Genomics — people studying genetics in songbirds, sea urchins, monkeys, microbes, fruit flies, and roundworms, for instance — often voice it privately. Others are eager to tell us what genes can’t do or warn that “precision medicine” will let us down. One of the world’s most respected geneticists, Britain’s Steve Jones, gives quite an entertaining lecture on our humble state of knowledge.“The more we learn, the less we understand,” he says. “We know almost nothing of genetics.”

The press, of course, too often falls hard for ludicrous memes such as “the slut gene.” But much of the time, the media is simply amplifying the signal sent by Big Genomics. Big Genomics outfits like the National Institutes of Health and the Broad Institute regularly assure us that their careful reading of the genome’s text will find crucial misspellings that generate disease — and let us revise, delete, or write around those errors.

Advertisements