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The Public Genome

Cheap sequencing technology will let you—and maybe the world—see your DNA

It’s April 2031, and a now 46-year-old campus politico of the class of 2007—pick your favorite—is in Manchester, N.H., to announce his intentions to run for U.S. president. After giving a morning speech, he heads to a local diner to grab a bite to eat and to chat with a few “ordinary” New Hampshirites. When he gets up to leave, someone quietly snatches the fork he had been using.

Two days later, national media outlets report that, based on tests done on the cheek cells left on the candidate’s utensil, he carries the gene that causes Huntington’s Disease, a fast-acting, highly degenerative neurological disorder that first appears in the patient’s middle-aged years. Doctors say chances are high that the diseases’ onset will come within the next five years. Under heavy pressure, he withdraws from the race, since there’s a good chance that he’d be unable to complete a term as president.

Welcome to the era of the public genome.

It’s a scenario that’s not terribly unlikely, assuming that research informally known as the “personal genome project” succeeds, which it appears well on track to do. The project is an offshoot of the Human Genome Project (HGP), a massive effort to determine the sequence of the human genome, that is, the 3 billion base pairs of DNA in human cells. The result of that effort was a consensus of many individuals’ genomes, and because the genome is nearly-identical among all humans, it was enormously useful for scientists to have any idea of what the “average” DNA sequence is.

What would be far more useful, however, is to know individual patients’ exact genomes. Why? First, it would allow physicians to screen patients’ entire genome for gene variants that predispose us for certain diseases—instead of ordering a volley of individual (read: expensive) tests for different disorders. Women who carry a gene variant known to increase breast cancer risk, for example, would be able to begin mammograms earlier in life. Second, it would allow physicians to personalize medical treatments. In a few cases, this is already possible. The breast cancer drug Tamoxifen is much more effective in individuals who produce a certain protein that digests drugs in a certain way. Treatments based on the DNA you carry, known as “personalized medicine,” offer a range of benefits over current treatments: more precise doses of potentially toxic drugs, better research into new drugs, and lower health care costs, according to a Mayo Clinic brief. And research into personalized treatments would accelerate if every individual possessed a readout of their own DNA.

The problem is money: decoding a genome is still too expensive. Today, the cost of is about $1,000 for a one-thousandth of the so-called “coding regions” of DNA, that is, DNA that actually codes for proteins. This already represents a huge drop in cost from the HGP, which finished in 2003 and cost $3 billion. The $1,000-threshold is important, says professor of genetics George M. Church, because at that point it becomes economical for many individuals to have their genomes sequenced. Church’s lab develops less expensive sequencing technologies and instruments, and he told me this week that he expects that, by the end of 2007, $1,000 will be the cost of sequencing 90 percent of coding DNA. (A disclosure: Church is my former professor and research advisor.)

The potential downside to this therapeutic boon is that you might not be the only person who gets to know what your genes are. Health insurance and life insurance companies might like to see your sequence before they offer you insurance, and they might adjust their prices based on heretofore hidden genetic minefields. Some employers might ask the same—who wants to hire a long-term employee with a genetic predisposition to an early-onset disease? And careful snoopers will likely be able to decode the DNA of anyone they can bring within spitting distance. “Just by sitting there, you shed dandruff and all kinds of stuff everywhere,” Church said. Guarding one’s DNA sequence against a persistent privacy invader would be nearly impossible.

Your genome—the stuff that tells each of your cells what to do—will no longer be just your business. What others can do with that information, however, will hopefully be limited by the law. Already, there is limited protection: The 1996 Health Insurance Portability and Accountability Act prevents some, but not all, group insurers from charging different rates based on genetic information, according to a 2006 Connecticut Law Review article by Seton Hall law professor Gaia Bernstein. What is needed is a more explicitly comprehensive law banning insurer and employer discrimination—like the Genetic Information Nondiscrimination Act (GINA), which passed the House of Representatives on Wednesday in a 420-3 vote.

With White House support in hand, GINA appears to set to become law. But there are several other challenges for society when individuals know their own DNA. Will lenders demand individuals’ genetic information and use it to discriminate against them? Will health care premiums rise when healthy-genomed individuals decided to forego insurance, and vice versa? And will concerns about the security and privacy of their genetic information dissuade many from self-sequencing in the first place?

There’s a good chance that being a public figure will mean having a public genome. With proper legal safeguards, personalized genomes will mean better medical care for most of us. But for many—especially the quasi-famous—one’s genes will be about as private as one’s pants.



Matthew S. Meisel ’07 is a chemistry concentrator in Currier House. His column appears on alternate Fridays.

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