26 August 2014
There is much excitement and feverish activity currently underway in the ever competitive world of DNA sequencing and analysis, driven by a potentially revolutionary USB DNA sequencing device that is no bigger than an average smartphone. The long-awaited Oxford Nanopore Technology (ONT) MinION has been made available for testing by selected researchers around the world who are rapidly discovering both the powers and limitations of this technology, and in the process providing vital feedback to ONT that should enable them to improve their devices.
While no data from these devices has yet appeared in the peer reviewed literature, there are nevertheless some early reports appearing online showing that not only are researchers being able to ‘read’ long single molecule DNA sequences (many kilobases in length) using these devices, but that these sequences, whilst still being far from as accurate as those produced by some more mature technologies, are likely nonetheless to be of sufficient quality to be useful. There are also now two papers available (from Nick Loman and Mick Watson ) that describe freely available tools to aid researchers in analysing the data that their MinION produces. These types of tools play a vital role in enabling downstream analysis of sequence data, and are a necessary prelude to the formal publication of the analysed data itself, which remains hotly anticipated
Does this mean the mobile DNA sequencing revolution is finally here?
It’s on its way, but these devices remain in the earliest stages of development, with significant throughput, reliability and accuracy challenges still to be overcome even before they enter mainstream use in research. Whether they will ever replace the high throughput sequencing platforms currently in use in most clinical laboratories remains to be seen.
What is the likely future impact of mobile DNA sequencing on healthcare?
This remains hard to predict. Small, portable, low cost DNA sequencers certainly have the potential to bring genomic medicine out of large centralised pathology laboratories and closer to the patient. Ultimately, if the goal of short run times coupled with accurate real time data acquisition and analysis from a USB device plugged into a laptop is realised, ‘bedside’ genomics becomes a possibility. The availability of mobile sequencing might also become particularly important for rapid genomic testing outside large-scale healthcare facilities, in community medical centres or as parts of mobile screening units.
The process of demonstrating the analytical validity, and most importantly clinical utility of these devices is, however, likely to be long and far from straightforward. We must also remember that sequencing is only a small part of the story of genomic medicine, and that the usefulness of rapid, near patient DNA sequencing will depend as much on the availability of rapid, automated sequence analysis and interpretation as it will on the sequencing itself.
These caveats aside, it is important to remember that the world’s first DNA sequencer in a USB stick is now up and running, and the future of ‘mobile genomics’ looks bright.