History, applications, methodological issues and perspectives for the use of environmental DNA (eDNA) in marine and freshwater environments.

Edgardo E. Díaz-Ferguson,Gregory R. Moyer

doi:10.15517/rbt.v62i4.13231

Abstract

Genetic material (short DNA fragments) left behind by species in nonliving components of the environment (e.g. soil, sediment, or water) is defined as environmental DNA (eDNA). This DNA has been previously described as particulate DNA and has been used to detect and describe microbial communities in marine sediments since the mid-1980's and phytoplankton communities in the water column since the early-1990's. More recently, eDNA has been used to monitor invasive or endangered vertebrate and invertebrate species. While there is a steady increase in the applicability of eDNA as a monitoring tool, a variety of eDNA applications are emerging in fields such as forensics, population and community ecology, and taxonomy. This review provides scientist with an understanding of the methods underlying eDNA detection as well as applications, key methodological considerations, and emerging areas of interest for its use in ecology and conservation of freshwater and marine environments.

Highlights

In order to understand distributions, patterns, and abundances for populations or species, the collection and identification of individuals from their physical origins must be undertaken
Species detection is fundamental to scientific disciplines such as phylogenetics, conservation biology, and ecology
Defined as short DNA fragments that an organism leaves behind in non-living components of the ecosystem, environmental DNA (eDNA) is derived from either cellular DNA present in epithelial cells released by organisms to the environment through skin, urine, feces or mucus or extracellular DNA that is the DNA in the environment resulting from cell

Summary

Wildlife DNA forensics

The field of wildlife DNA forensics, which is a synthesis of conservation genetics and forensic genetics, was developed to address the increasing need of DNA forensic tools in wildlife law enforcement (Ogden, 2008, 2009). The applicability of eDNA as a forensic tool appears promising to address basic forensic identification issues at the level of individual (e.g., hatchery vs wild origin, location of origin, species introduction), population, or species. Detection of eDNA fragments can provide evidence for illegal wildlife trade and traceability of illegal fishing products (e.g., shark or rayfins)

Detection of low density populations

Biodiversity and community structure

Water contamination