The Oxford Nanopore Minion: A Tool for Combatting Illegal Logging of White Oaks?

Illegal logging is a global problem with large economic, environmental, and social costs. A high proportion of illegal trade is channeled through China, the largest importer of raw logs and the largest exporter of hardwood products. The complexity of illegal trade is highlighted by Mongolian white oak, an important hardwood for flooring and furniture. Mongolian oak from the Russian far-east is often illegally harvested and processed in China, and illegally-sourced lumber is mixed with legally-sourced Chinese and American white oaks. These species cannot be discriminated using anatomy, stable isotopes, or wood chemistry, so the mixtures are distributed to consumer markets under the name of a legally harvested (often American) white oak species.

We are testing whether the Oxford Nanopore MinION can identify diagnostic genomic variation that defines Old and New World white oaks. Given its portability, the MinION has the potential to be used for validating taxonomic identities and source labels of lumber from remote locations where DNA sequencing is not available. Based on a sample of >70,000 MinION reads (110+ Mbp) from North American white oak DNA, chloroplast genome sequences can be identified from the read pool, despite the rarity of the this genome in total DNA (~1%). The average length of mapped sequences was 1.5 kb, although reads up to 11.3 kb were also mapped. 2D reads show an average identity to the reference of 81%. Given sufficient sequencing depth, this level of accuracy should be sufficient to classify oak wood to hemisphere-of-origin.