
Environmental DNA (eDNA) has been used to quantify the proportion of Japanese native common carp to non-native strains from the Eurasian continent. This method is based on single nucleotide polymorphism (SNP), and it is hoped that this novel approach will facilitate the detection of non-native genotypes in various species.
http://www.sciencedaily.com/releases/2015/09/150907101202.htm