Expecting a new sequencing company to release raw data along with big claims was not unusual in the Mesozoic era of next-gen genomics, but then Oxford Nanopore evolved into existence. Thankfully, other nanopore companies are not following the same marketing model. A new nanoscale company named Quantum Biosystems went public with their instruments today along with a data release page.
This Japanese company likely follows the method published in Nature Scientific Reports in 2012, where its authors demonstrated the sequencing of let-7 microRNA molecule using their technology.
Two paradigm shifts in DNA sequencing technologiesfrom bulk to single molecules and from optical to electrical detectionare expected to realize label-free, low-cost DNA sequencing that does not require PCR amplification. It will lead to development of high-throughput third-generation sequencing technologies for personalized medicine. Although nanopore devices have been proposed as third-generation DNA-sequencing devices, a significant milestone in these technologies has been attained by demonstrating a novel technique for resequencing DNA using electrical signals. Here we report single-molecule electrical resequencing of DNA and RNA using a hybrid method of identifying single-base molecules via tunneling currents and random sequencing. Our method reads sequences of nine types of DNA oligomers. The complete sequence of 5?-UGAGGUA-3? from the let-7 microRNA family was also identified by creating a composite of overlapping fragment sequences, which was randomly determined using tunneling current conducted by single-base molecules as they passed between a pair of nanoelectrodes.
The newly released data also includes 2001 signal points from let-7 along with a pdf file with description of base-calling and other methods. For base-calling, the company uses hidden Markov model with transition probability from one nucleotide to the next. We wonder, whether the BlindCall approach discussed last week would be appropriate for their technology. That leads to the more important question of whether de- multiplexed single electrical signal can achieve the same error rate as four- color signals from competing technologies. Hopefully, the company will share more data on longer DNA molecules for researchers to play with.