DNA Barcoding in lesser known threatened ichthyofauna to augment conservation effort
Department Of Biotechnology, Gauhati University
Shamim Rahman, Amalesh Dutta And Mohan Chandra Kalita
Introduction: What conservation problem or question does your study address?
Unambiguous characterization of threatened species is imperative as they are the quickly traceable indicator of biodiversity degradation and deserve immediate attention. This study deals with development of DNA barcodes in lesser known threatened fish species of Assam, which is part of biodiversity hotspot, for quick and flawless tagging of species in peril leading to expansion of conservation efforts as it brings to light new data and probable mode of remedy.
Methods: What were the main research methods you used?
The methods include both conventional and molecular taxonomy comprehending complementary approach of one to another. Conventional taxonomy starts with collection of species mostly in commercial fishing grounds, followed by counting of morphometric parameters utilizing vernier caliper, meristic counts, cataloguing and vouchering and utilization of informatics to construe morphomtric data. Molecular section includes total genomic DNA isolation, amplification of target region (e.g. partial mtCOI region), sequencing and sequence analysis using bioinformatics. Developed DNA barcodes for species level discrimination are used for characterization such as nucleotide frequencies, GC content phylogenetic significance etc. Diverse fish groups are targeted in this ongoing research since 2011 and another one year is estimated for characterization of more than one groups.
Results: What are your most important results?
This study established few DNA barcodes for the first time in species or first time from this region. Substantially more nucleotide change occurred at 3rd codon position in comparison to first and second. No transversional pairs observed at 1st and 2nd codon positions indicating most synonymous mutations occurred at the 3rd codon positions of the sequences. Geographical similarity revealed from this study indicating role of DNAB in population level discrimination.
Discussion: What are your important discussion points and what is the relevance of your results to conservation (if any)?
DNA barcoding was applied at every stage of life with success. Thus, monitoring of unlawful fishing and detection of of invasion of exotic species are possible with trace amount of fish part or with eggs and fingerlings. Findings from this research can be utilised for population genetic analysis, detecting status of the species and tracking of migratory fish population for conveying the knowledge to policy makers for planning conservation strategies for fishes.