DNA barcodes - Revolution in organism classification?

The consumer product barcode is a small code but helps to retrieve information about the product with almost absolute accuracy. In science, life also has a similar concept - DNA bar codes, built from the most basic material of life, DNA.

Simple, but many applications

The concept of DNA barcoding has been widely known since the early 21st century, when Canadian scientists presented their study of using a gene segment of 648 nucleotides from the mitochondrial genome - called Co1 - to identify 260 birds and propose to use it as a "barcode" to store and standardize animal information.

The use of DNA in qualitative research is not a new idea, since humans have known DNA since 1953. DNA barcode breakthroughs lie in its standardization and synchronization. This means that for any organism, just decode the Co1 gene (or a very small number of genes and predetermined), compared to existing DNA libraries, it is possible to identify the species and identify it. new species.

Traditional classifications will be replaced by DNA barcodes.(Photo: Jewishgenetichealth).

DNA barcodes are enthusiastically responded by scientists. Many people believe that this tool will mark the "revival" of the field of traditional organism classification. It is expected to help realize organism classification from different stages of the life cycle or from individual body parts, facilitating the discovery of new species, promoting the formation of prize technology. Hand-held DNA sequences applied in the field of biodiversity and help to further study the diversity of life.

In February 2005, at the conference on building bar codes at the Natural History Museum London, England, scientists agreed to implement the " Initiative to build barcodes of life" with ambition. quickly store information of about 10 million species of organisms on Earth with DNA barcodes.

DNA bar codes have become a research area that has a huge amount of funding and is widely implemented. It is possible to witness the development of this "industry" through the creation of the Life Barcode Construction Federation (CBOL), the International Federation of Barcode Symbols (iBOL) and the Code of Database. life bar (BOLD). In the period of 2003-2010, there were 411 scientific articles containing "DNA barcodes" in the title and this tool was used in many areas, from identifying the life cycle stages to testing Check and supervise fish sold in the market.

How big is the power?

According to many scientists, DNA barcodes are not necessarily universal keys. Some authors emphasize that DNA barcodes cannot provide sufficiently reliable information to classify at a higher level than species. On the contrary, others claim that it is unusable for the species level, but is still usable for higher classification groups.

Many people claim that DNA barcodes simplify the classification of work. Even, the author straightened out that the idea of ​​replacing traditional classifications with DNA barcodes gives "more bad things than good". Such harsh criticisms are extremely rare in scientific life.

Technically, some are skeptical about the accuracy and applicability of the selected DNA sequences as "bar codes". Many studies have shown that the sequences of Co1 gene did not produce satisfactory results when building a set of symbols on mushrooms and suggesting another piece of DNA - ITS - for this group. Interestingly, with the emergence of DNA barcodes, researchers have for decades focused on identifying with short DNA sequences on fungi.

DNA barcodes greatly simplify the work of taxonomists.

The value of DNA sequencing library will be the weakness of DNA barcode ideas in the future. A new sequence of decoding only makes sense when compared to the bank containing the available sequences, valid enough to be reliably compared and large enough to compare.

While waiting for that data bank, efforts to build barcodes merely add data without much convincing applications. On the other hand, BOLD data shows that until 2011, only 145,298 species have been described as valid bar codes, compared to 1,493,132 bar code data uploaded to the database, proving the non-optimal resource distribution. .

The performance of the "industrialization" idea of sorting organisms by barcode is also a controversial point. For many scientists, because the world's biodiversity is largely unknown, DNA barcodes indicate only the existence of a new species or group, but not the power to describe new species or analyze. about categories. Therefore, instead of accelerating the process of biodiversity research, this tool only increases the workload for researchers.

Despite criticism, DNA barcodes are still a research focus with more and more published numbers, many of which have important value.