In 1965, Gordon Moore predicted that the trend governing the rapid increases in computing power he had observed — that it was increasing roughly by a factor of two each year — would continue, if not increase, through at least 1975. Since that time, his prediction — dubbed Moore's law in 1970 — has proven to be remarkably accurate when applied to electronic devices, particularly those that contain chips or sensors.
Though the rapidly declining cost of DNA sequencing has already surpassed it, Ion Torrent's founder and CEO Jonathan Rothberg says Moore's law now applies to the chips that are the basis of his firm's non--optical DNA sequencing technology. In a July Nature paper, Rothberg and his colleagues detail the company's electronic approach, which uses semiconductor-sensing ion chips to monitor the release of hydrogen ions during nucleotide incorporation. This approach is the basis of Ion Torrent's approximately $50,000 desktop machine, called the Ion PGM. Life Technologies acquired Ion Torrent last year.
"Like the PC made computing ubiquitous, the semiconductor ion sensor at the heart of our technology will make sequencing ubiquitous," Rothberg says.
To demonstrate the technology's utility, Rothberg et al. report in their paper three bacterial genomes they sequenced at five- to 10-fold coverage. For each, the researchers say they routinely generated 100-base read lengths. According to Rothberg, the team sequenced each bacterial genome in two hours, though each run required about six hours of prep time.
Rothberg says this sequencing technology is not only speedy, but cheap. "We build the chips [used] in the paper with a 1995 semi-conductor factory, or foundry," he says. "When you use a 2005 foundry, you get 100- to 250-times more sensors — and sequence — for the same chip cost."
To demonstrate the capability of this technology to sequence human genomes, the team also reports a low-quality genome sequence for Moore — the Intel co-founder famous for his eponymous law — in which it identified 2,598,983 total SNPs, around 3 percent of which were novel. In its paper, the Ion Torrent team said its work "suggests that readily available [complementary metal-oxide semiconductor] nodes should enable the production of 1 billion sensor chips and low-cost genome sequencing."
"Gordon [Moore] was done on our first little chips for around $50,000," Rothberg says, adding that "future chips will bring this below $1,000."
At the Consumer Genetics Conference held in Boston in June, Rothberg said he expected Ion Torrent will be able to sequence a human genome for $1,000 by January 2013, and for $500 that July. Now, he says, the company is "on track on all fronts" to meet those predictions.
"Moore's law has been good for over 40 years," he says. "We have [the] advantage of using 40 years of this accumulated [evidence]."