The barcoding concept has been implemented previously using Raman spectroscopy for the classification and identification of complex biological materials.
The 2D barcoding concept has potential application in a natural product discovery project, allowing for the rapid dereplication of known compounds and as a tool in the search for structural novelty within compound classes with established barcodes.
Inevitably, with any single marker, or even a combination of several [ 68], there will be some species or groups for which it simply does not work, and this has been recognized from the beginning of the DNA barcoding concept [ 3].
Finally, it has been shown that woody plant lineages show consistently lower rates of molecular evolution as compared with herbaceous plant lineages [37], suggesting the application of DNA barcoding concepts should be more difficult for tree floras than for non-woody floras [26], [38].
Coissac, E., Hollingsworth, P. M., Lavergne, S. & Taberlet, P. From barcodes to genomes: extending the concept of DNA barcoding.
Here, we introduce the concept of barcode tiling in order to analyze pooled shRNA screens.
One of the major criticisms of DNA barcoding is the species concept that it implements [ 54].
The ABGD method [ 39] still suffers from limitations based on the genetic distance concept and barcoding gap discussed above, but presents a major advantage since it is applicable as an independent tool without an a priori species hypothesis.
In a sense, it could be said that barcoding in this situation is more similar to traditional morphological identification- with each specimen evaluated separately, and requiring individual attention from a person with specialized training- than to the original concept of barcoding as the mass processing of thousands of samples by technicians with a relatively low level of expertise [ 58, 59].
