More than 20 years after scientists first released a draft of the human genome sequence, the long-awaited book of life has been rewritten.
A more accurate and comprehensive version of the genetic code was published Wednesday, marking a major step toward a deeper understanding of human biology and personalized medicine for people from a wide range of racial and ethnic backgrounds.
Unlike the previous reference — which was based largely on the DNA of a mixed-race man from Buffalo, with input from a few dozen other individuals, mostly of European descent — the new “pangenome” includes near-complete genetic sequences from 47 men and women from Diverse ancestry, including African American, Caribbean, East Asian, West African, and South American.
The regenerated genome map is a crucial tool for scientists and clinicians hoping to identify genetic variations associated with disease. It also promises to provide treatments that can benefit all people, regardless of race, ethnicity or ethnicity, the researchers said.
“It’s been needed for a long time — and they’ve done a very good job,” said Ewan Birney, a geneticist and deputy director general of the European Molecular Biology Laboratory, who was not involved in the effort. “This will improve our nuanced understanding of diversity, and then this research will open up new opportunities for clinical applications.”
Powered by the latest DNA sequencing technology, pangenome brings together all 47 unique genomes into a single resource, providing the most detailed picture yet of the code that powers our cells. The gaps in the previous reference have now been filled in, with approximately 120 million previously missing DNA letters added to the three-billion-character code.
Gone is the idea of a totemic string of DNA extending six feet when coiled and stretching in a straight line. Now, the rebooted reference is like a corn maze, with alternate paths and side paths allowing scientists to explore a broader range of genetic diversity found in people around the world.
Dr. Eric Green, director of the National Human Genome Research Institute, the government agency that funded the work, likens these cracks to a new kind of bodywork guide for auto repair shops. Whereas previously, each mechanic had a design specification for only one type of car, now there is a master scheme covering different makes and models.
“We went from having one really cool blueprint Chevy to having the blueprints for 47 representative cars from each of 47 different manufacturers,” he said.
Figuring out what to do with the Kelly Blue Book of Genomics will involve a steep learning curve. New analytical tools are needed. Coordination systems must be redefined. Widespread adoption will take time.
“Making this user-friendly by the community is a work to be done,” said Heidi Rehm, chief genomics officer at Massachusetts General Hospital in Boston, who was not involved in the project.
But experts said that in time, the pangenome will revolutionize the field of genomic medicine.
“We would benefit from actually understanding ourselves as a species much better,” said Evan Eichler, a genomics scientist at the University of Washington. Dr. Eichler was among more than 100 scientists and bioethicists Description of the new pangenome reference in Nature magazine.
Project engineers continue to add more populations, aiming to include at least 350 high-quality genomes that encompass the bulk of global human diversity.
“We want to represent all branches of the human tree,” said Ira Hall, a geneticist who leads the Yale Center for Genomic Health.
Some of the new genomes will come from New Yorkers who previously participated in a research program at the Mount Sinai Health System. If their raw DNA data appeared to reflect certain under-represented genetic backgrounds, those individuals would be invited to participate in the pangenome project.
Some gaps in the publicly available reference may not be filled, despite the design.
Previous attempts to capture human genetic diversity have often extracted sequence data from marginalized populations without considering their needs and preferences. Building on those ethical missteps, pangenome curators are now collaborating with Indigenous groups to develop formal policies around data ownership.
“We’re still grappling with the issue of indigenous and tribal sovereignty,” said Barbara Koenig, a bioethicist at the University of California, San Francisco, who was involved in the project.
In Australia, researchers are merging DNA sequences from various indigenous peoples into a similar repository that will be integrated with an open-source pangenome, but then kept behind a paywall. According to Hardip Patel of the Australian National Center for Indigenous Genomics in Canberra, the scientists next plan to consult with community leaders about whether or not to make the data available through request.
Some indigenous advocates want to see the pangenome project go even further. Keolu Fox, a genomics scientist at the University of California, San Diego, who is an indigenous Hawaiian, has proposed training the next generation of Indigenous scientists to have greater agency over genomic data.
“It’s time we finally decentralized power and control and redistributed that among the communities themselves,” said Dr. Fox.
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