March 31, 2010 | 4
The first sequenced drafts of the human genome were announced 10 years ago this June. President Bill Clinton remarked at the time that, "genome science will have a real impact on all of our lives." Although hopes were high, neither he nor the researchers involved promised magical genomic cures or personalized genomes for everyone by 2010. So when exactly can we, as individuals, expect to see that impact?
The field of medical genetics today is in a far different place than many predicted back then. Some of the advances, including lightning-fast sequencing, were unexpected accomplishments, but on other fronts, such as personalized treatments, progress has been disappointing.
Despite nearly a decade’s time for researchers to pore over the human genome, "the consequences for clinical medicine…have thus far been modest," director of the National Institutes of Health Francis Collins wrote in an editorial published online in Nature March 31 (Scientific American is part of Nature Publishing Group). And as former director of the Human Genome Project, he continued to note that, "it is fair to say that the Human Genome Project has not yet directly affected the health care of most individuals." As one of the few who has had their genome sequenced, Collins described the experience as "riveting, despite the limited clinical validity and utility of many of [the] predictions."
The superiorities of genetic tests that have been touted as good predictors of disease predisposition, such as those for BRCA1 and BRCA2 mutations that are linked to breast and ovarian cancer, are being doubted by some researchers who favor family history evidence.
"There is still some way to go before this capability can have a significant effect of medicine and health," J. Craig Venter, a researcher and entrepreneur whose former company, Celera Genomics, sequenced the human genome in 2000, wrote in an accompanying editorial.
Currently few more than a dozen people have had their full genome sequenced. The 1,000 Genomes Project, an international consortium, aims to make that number top a thousand by next year. After the human code was deciphered, the genomes of everything from tumors to zebra finches have followed. In fact, more than 2,000 other species now have had their genomes sequenced, Venter noted.
If clinical treatments and diagnoses have been slow to emerge from the genomics revolution, its impact on scientific process itself is becoming increasingly apparent. Thanks to speedy sequencing and high-powered computing, 100 billion base pairs of DNA code can now be sequenced in a single day, Venter pointed out. Such robust—and increasingly affordable—processing capabilities have restructured how many labs do research, explained Todd Golub, director of the Cancer Program at the Broad Institute, and Robert Weinberg, of the Whitehead Institute for Biomedical Research at the Massachusetts Institute for Technology, in respective Nature editorials. Golub described the sweeping tumor genome scans that have looked for common mutations and then "moved rapidly into testing drugs that target the mutated proteins—often without extensive understanding of the underlying biology." Weinberg, however, cautioned that specific, hypothesis-based inquiries should not be entirely pushed aside in favor of flashier genome-wide hunts.
Regardless of where genomics takes laboratories and medicine in the next 10 years, those in the field agreed that this past decade will likely turn out to be a prelude to impressive human-health applications to come. "The genome revolution is only just beginning," Venter wrote. Collins, however, was more guarded, asserting possibility over guarantee, concluding that, "The promise of a revolution in human health remains quite real."
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