Improving molecular techniques for detecting Asian carps: Using LAMP technology to make it portable and faster
Dates
Start Date
2015
Summary
Description of Work The field portion of a method validation study was completed August 2015. The study was designed to test the accuracy of a LAMP method to detect eDNA of Asian carps during simulated fish transport. During the study, more than 10,000 minnows were held in each of three fish transport tanks. Ten 4-inch silver carp were placed in one tank, a single 4-inch silver carp in the second tank while the third tank had no silver carp and served as a negative control. The LAMP method used amplifies the DNA of both bighead carp and silver carp. Three replicate trials were completed on separate days with side-by-side analyses completed by three novice and two expert users. Expert users had extensive experience completing laboratory-based [...]
Summary
Description of Work
The field portion of a method validation study was completed August 2015. The study was designed to test the accuracy of a LAMP method to detect eDNA of Asian carps during simulated fish transport. During the study, more than 10,000 minnows were held in each of three fish transport tanks. Ten 4-inch silver carp were placed in one tank, a single 4-inch silver carp in the second tank while the third tank had no silver carp and served as a negative control. The LAMP method used amplifies the DNA of both bighead carp and silver carp. Three replicate trials were completed on separate days with side-by-side analyses completed by three novice and two expert users. Expert users had extensive experience completing laboratory-based genetic and molecular methods whereas novice users included two conservation officers and a geospatial studies student, all with minimal to no genetics or molecular experience. Water samples were tested from tanks at multiple time points to determine how long a silver carp needs to be present before it can be detected. Additional samples are being processed to compare the LAMP method and laboratory-based Asian carp eDNA methods and to determine the optimal number of replicates for the LAMP method to maximize detection of Asian carp eDNA.
Relevance & Impact
If successful, the LAMP method will allow end users to take the power of eDNA amplification and detection from the laboratory to the field, significantly decreasing the time to obtain results and thus enhancing the utility of this powerful tool. By simplifying sample collection, preparation and analysis, the LAMP method and supporting amplification system may allow even novice users with only minimal training and without expertise in a genetics or molecular laboratory to collect and analyze eDNA samples in less than one hour. These key advantages could provide a critical tool to provide managers with the critical and timely information needed to make time-sensitive decisions to help prevent the spread of invasive species or pathogens.
Key Findings
Coming soon - data analyses are in progress.
Products
Oral presentation "A New Tool to Rapidly Detect Invasive Species in Transport as Bait," 2015 Fall Great Lakes Law Enforcement Committee meeting; Windsor, Ontario, Canada.
Upcoming: Manuscript on the new technology to be published in 2016
A peer-reviewed publication will be prepared when data analyses are completed.
Aquatic invasive species are a significant concern, because they can cause environmental and economic damage. Preventing their spread is imperative to successful integrated pest management efforts, and the detection of environmental DNA (eDNA) has become an important surveillance method to detect the presence of Asian carps (bighead carp – Hypophthalmichthys nobilis and silver carp – Hypophthalmichthys molitrix) and other aquatic invasive species. However, most current methods to detect Asian carp eDNA (and DNA of other species) require specialized laboratories and equipment. Although the time to process eDNA samples in the laboratory is being reduced, the availability of a fast, point-of-need DNA detection tool could be very useful for certain applications for both research and natural resource management agencies. For example, water samples could be processed in the field to help guide more extensive, laboratory-based, eDNA surveillance sampling efforts or to detect the presence of Asian carp in other locations such as in a fish transport tank. In partnership with Middleton, WI-based Lucigen Corporation, USGS is evaluating a loop-mediated isothermal amplification (LAMP) method that, when used with a portable amplification system, detects eDNA of Asian carps from water samples in as little as one hour (includes sample collection, processing, amplification and detection). Rapid eDNA-based detections of Asian carps (and of other species or pathogens) will provide managers near real-time information to support critical decisions in quick-response actions to stop the spread of invasive species and diseases.