In Oxford Nanopore's 'strand sequencing' method, a single-stranded DNA polymer is passed through a protein nanopore, and the sequence of individual DNA bases on the strand are identified as it passes through.
The strand sequencing method is deployed on the Company's GridION platform; strand-sequencing nanopore/enzyme constructs are provided in the single-use cartridge. Oxford Nanopore uses proprietary designed nanopores and enzymes constructs to achieve strand sequencing. Oxford Nanopore will be presenting further information about this technology at the AGBT conference on 17th February 2012.
Challenges in strand sequencing include:
When a DNA polymer passes through a nanopore, a number of individual DNA bases occupy the aperture of the nanopore at any time. A successful method of DNA sequencing must identify the sequence of individual bases on this strand.
A method of controlled translocation of the strand through the nanopore is needed.
Oxford Nanopore has not yet disclosed proprietary technical information on this method, however various publications from Oxford Nanopore collaborators describe work done outside the Company to solve these problems. In 2010, two publications from Professor Hagan Bayley's laboratory described successful identification of DNA bases on ssDNA and identification of the modified bases methylC and hydroxymethylC. Regarding controlled translation of the DNA, in 2010 Professor Mark Akeson published a landmark study demonstrating enzyme-controlled translocation of a DNA polymer through a nanopore in conditions commensurate with a DNA sequencing technology. Further publications can be found here.
These and other techniques have been developed by Oxford Nanopore's high-throughput electronic sensing platform into a strand sequencing technology. Oxford Nanopore has not signed a commercialisation agreement for strand sequencing at this time.
Oxford Nanopore has a broad IP portfolio encompassing the use of nanopores for DNA sequencing and other applications. For more information click here.
