Timber DNA release using focused ultrasound extraction (FUSE) for genetic species identification

The use of genetic data for timber species and population assignment is a powerful tool for combating the illegal timber trade, but the challenges of extracting DNA from timber have prevented the routine use of genetics as a supply chain management tool. To overcome these challenges, we explored the feasibility of focused ultrasound extraction (FUSE) for rapid DNA release from timber. Using high-pressure ultrasound pulses, FUSE generates a cavitation bubble cloud that disintegrates samples into acellular debris, resulting in the mechanical release of DNA. In this work, FUSE was applied to white oak (Quercus alba) timber shavings to test the feasibility of using FUSE for timber DNA extraction for the first time. Results showed that FUSE processing disintegrated the tissue samples and released significant quantities of DNA. After five minutes of tissue processing DNA quantities of 0.21 +/- 0.02 ng/mg, 0.99 +/- 0.32 ng/mg, and 0.14 +/- 0.01 ng/mg, were released from medium, coarse, and combination shaving groups, respectively. Amplification and sequencing of regions within the matK and rbcL chloroplast genes confirmed that the quality of DNA prepared with FUSE was suitable for PCR and short-read sequencing applications. Overall, these results show that FUSE can serve as a DNA sample preparation method capable of releasing high-quality DNA from timber in a fraction of the time required by conventional extraction methods. Based on the improved efficiency of DNA release with FUSE, ongoing work aims to develop this technology into portable systems that can be used to rapidly prepare timber samples for genetic species identification.