Long-reads sequencing is once again at the forefront, writes Michael Eisenstein at Nature Biotechnology. A few years ago, Pacific Biosciences made a splash at the 2010 Advances in Genome Biology and Technology meeting with its RS machine, which it said at the time could produce sequences as long as 20,000 bases. However, as Eisenstein notes, the approach was limited by a low throughput and high error rate.
The company, though, has improved its machine, and other companies are hot in pursuit. Talks at AGBT this year, Eisenstein says, showed that a PacBio approach could be applied to de novo sequence assembly of repetitive genomes as well as to elucidate structural variations. "In the past year, the read lengths have improved by a factor of four," Michael Schatz from Cold Spring Harbor Laboratory tells Nature Biotechnology. "If this were Apple, they would have branded it as a new model — it really feels like a new instrument."
At the same time, Illumina and Nabsys are developing long-read sequencing capabilities. Illumina acquired Moleculo earlier this year, and that technology is slated to launch this summer. It, too, has been used to sequence a de novo, repetitive plant genome, Eisenstein notes. While it has its drawbacks in dealing with GC regions, CSHL's Schatz notes that there is time for improvement before its launch. And Nabsys says that its semiconductor-based system will allow for fast and precise sequencing.