Scientists sequence a whole genome to identify a plant species within hours

Over the last forty years, DNA sequencing has revolutionised the scientific world but has remained laboratory-bound. Using current methods, a complete experiment to identify a species, from fieldwork to result, could easily take a scientist months to complete. 

Species identification is, by nature, a largely a field-based area of pursuit, thereby limiting the pace of discovery and decision making that can depend upon it. Using new technology to identify species quickly and on-site is critical for scientific research, the conservation of biodiversity and in the fight against species crime.

In new study, Kew scientists used the portable DNA sequencer, the MinION from Oxford Nanopore Technologies, to analyse plant species in Snowdonia National Park. This was the first time genomic sequencing of plants has been performed in the field.

This technology, commercially launched in 2015, has since been used in Antarctica, in remote regions affected by disease, and on the International Space Station.

One of the successes illustrated in the paper is the field identification of two innocuous white flowers, Arabidopsis thaliana and Arabidopsis lyrata ssp. petraea. This was achieved by sequencing random parts of the plants' genomes, avoiding the tricky and time consuming process of targeting specific pieces of DNA which is the more traditional approach for identifying species with DNA.

The researchers compared their new data to a freely available database of reference genome sequences to make their identification. Crucially, replicating their experiment in Kew's Jodrell Laboratory with other DNA sequencing methods allowed them to devise sophisticated statistics to understand the useful properties of this new kind of data for the first time.