A new DNA reader could bring genetics to medical clinics.
After years of predictions that the “$1,000 genome” – a read-out of a person’s complete genetic information for about the cost of a dental crown – was just around the corner, a U.S. company is announcing Tuesday that it has achieved that milestone and taken the technology several steps ahead.
The new genome-sequencing machine from Ion Torrent, a division of Life Technologies Corp. (LIFE.O), in Guilford, Connecticut, is 1,000 times more powerful than existing technology, says CEO and chairman Jonathan Rothberg.
Taking up about as much space as an office printer, it can sequence an entire genome in a single day rather than six to eight weeks required only a few years ago. The new sequencer, says cardiologist Eric Topol, chief academic officer of private California hospital and doctor network Scripps Health, “represents an exceptional advance and can change medicine.”
Ion Torrent will sell the tabletop machine, called the Ion Proton Sequencer, for $99,000 to $149,000, making it affordable for large medical practices or clinics; existing sequencers cost up to $750,000. The computer chip and biochemicals to sequence a genome will cost $1,000, compared to, for example, $3,000 to test for mutations just in the BRCA genes that raise the risk of breast and ovarian cancer and $5,000 for a complete genome sequencing by Ion Torrent competitor Illumina Inc (ILMN.O).
For a graphic on the shrinking cost of genome sequencing, see: link.reuters.com/xys85s
For now, Rothberg expects research labs to be his main customers, using Proton to obtain the complete genome sequence of people with cancer or autism, for instance, and thereby elucidate a disease’s underlying genetic causes as well as possible ways to treat it. The company has signed on Baylor College of Medicine, Yale School of Medicine and the Broad Institute as its first customers.
Other scientists and physicians, however, say the long-awaited arrival of the $1,000 genome opens the door to widespread whole-genome sequencing even of people who are not ill. And that raises ethical, legal, and medical issues that experts are only beginning to grapple with.
“I’m a big proponent of bringing genetics into the clinic,” says Thomas Quertermous, chief of the division of cardiovascular medicine at Stanford University and an expert in the genetics of heart disease. “But it has to be done in a timely way, and not before its time.”
Babies might be first in line for whole-genome sequencing. Every state requires newborns to be screened for at least 29 genetic diseases.
“If the cost of whole-genome sequencing gets sufficiently low, you could sequence all the genes in a newborn” for less than the individual tests and follow-ups required when one comes back positive, says Richard Lifton, chairman of the genetics department at Yale University. “I’m increasingly confident that’s going to happen. But we need to be careful how we utilize this information. Do you tell a newborn’s parents his apoE status” — that is, whether he has the form of a gene that raises the risk of Alzheimer’s disease?
The cost of whole-genome sequencing will continue to plummet. Lifton foresees a “zero-dollar genome,” making it likely that “we will just do it as part of routine clinical care” for children and adults. A Yale team led by Murat Gunel has already used partial genome sequencing of the 1.5 percent of the genome, called the exome, that codes for proteins to determine the cause of a mysterious and still unnamed genetic disease that results in severe brain malformations.
Because no genes had been identified as causing the malformation, it was not possible to do a standard genetic test, which reveals whether a particular gene is normal or mutated. But exome sequencing showed that a previously unknown gene on chromosome 19 is responsible, he and colleagues reported in 2010. “The new Proton instrument is a big step up,” says Lifton. “It promises to markedly increase the speed and reduce the cost of genome-level sequencing.”