Jornal de Biomarcadores Moleculares e Diagnóstico

DNA Barcoding and Phylogenetic Relationships of Nine Catfish Species from Mekong Basin, Vietnam

Abstract

Ha Thi Thuy Tran, Thi Nga Tran, Hang Nguyen Ai Tran and Huong Thi Nguyen

Fishes that belong to the family Pangasiidae are widely recognized to have good potential for aquaculture and are highly valued as flesh food in the markets of Vietnam. However, there is much debate on the identification and phylogeny of the available species of Pangasiidae in the Asia. In the present study, nine species of two genera (Pangasianodon and Pangasius) of Pangasiidae were investigated using two partial sequences of the COI and cytochrome b mitochondrial genes to differentiate among them and study their phylogenetic relationships. A total of 42 haplotypes were identified (21 haplotssypes of each gene). The highest interspecies genetic distance was between Pangasius larnaudii and Pangasius bocourti (0.189) for COI and was between Pangasius macronema and Pangasianodon hypophthalmus (0.179) for cyt b. Whereas the lowest genetic distance was between Pangasius macronema and Pangasius conchophilus for both genes (0.65 for COI and 0.92 for cyt b, respectively). The phylogenetic tree analyses of two genes showed two major clusters that are genetically distant from the two genera. The results obtained in this study also show that beside COI gene, the cyt b gene region can be successfully used for differentiating between species and accepted as a standard region for DNA barcoding.