DNA barcoding of freshwater fishes of Bangladesh

• Published in: Genome Vol. 60; no. 11; p. 904
• Main Authors: Ahmed, Sagir M, Nahar, Luthfun, Sanzida, Nusrat J, Akter, Aysha J, Dina, Sabrina R, Islam, Nafisa N
• Format: Journal Article
• Language: English
• Published: Ottawa Canadian Science Publishing NRC Research Press 01.11.2017
• Subjects: Agricultural management; Biodiversity; Cryptic species; Cytochrome-c oxidase; Deoxyribonucleic acid; DNA; DNA barcoding; Environmental degradation; Fish; Fishing; Fishing gear; Fresh water; Freshwater fish; Gene sequencing; Habitat loss; Habitats; Human populations; Overfishing; Spawning; Species; Bangladesh
• ISSN: 0831-2796

Background: The rapid increase in human population, and the subsequent intensification of agricultural, industrial, and infrastructural activities, along with deficient management, have led to the destruction of habitat, ecosystem, and biodiversity. Overfishing, the use of destructive fishing gear, and the catching of spawning and undersized fish are the main causes of loss of fish diversity and production in Bangladesh. The country has already lost more than a dozen vertebrate fauna during the last century. The lack of a proper database on the biodiversity is one of the greatest impediments for the utilization and safeguarding of our interests. The country needs to maintain the genetic identity and integrity of species in their natural habitats. Results: This study represents the first comprehensive molecular assessment of freshwater fishes from Bangladesh. We analysed cytochrome c oxidase I (COI) gene sequences for 78% of the species mentioned in the current Bangladesh Red List. Barcodes were obtained from 350 specimens, representing 195 species of freshwater fish belonging to 12 orders and 57 families. The average Kimura two-parameter (K2P) distances within species, genera, families, and orders were 0.32%, 15.83%, 19.14%, and 25.06%, respectively. DNA barcodes discriminated congeneric species without any confusion, and some new cryptic species have been explored. Significance: This is the first effort to compile a reference library of DNA barcodes that provides species-level identifications for freshwater fishes of Bangladesh. The study strongly validates the efficiency of COI as an ideal marker for DNA barcoding of Bangladesh freshwater fish.