Molecular identification and phylogenetic relationship of Bangladeshi
pufferfish based on mitochondrial COI and 16S rRNA genes
Abstract
Pufferfish is common in marine, brackish and freshwater habitats in
Bangladesh. Pufferfish poisoning sporadically occurs due to the
consumptions of toxic pufferfish throughout the country. A study was
conducted for molecular characterization and phylogenetic analysis of
Bangladeshi pufferfish using two markers, mitochondrial cytochrome c
oxidase I (COI) and 16S ribosomal RNA (16S rRNA) genes. A total of 34
barcode sequences (19 COI & 15 16S) from 30 collected specimens
representing six species and four genera. The mean length of the
sequences were 644 bp and 613 bp for COI and 16S, respectively. The
average %GC content was 50.06 for COI which was higher compared to the
16S rRNA (46.61). Average Kimura two parameter (K2P) distances within
species was found as 0.29 ± 0.01 for COI and 0.70 ± 0.06 for 16S rRNA.
The Maximum Likelihood (ML) phylogenetic analysis of COI and 16S rRNA
gene sequences revealed that the corresponding species were clustered
together in the same clade. Cluster sequence analyses result revealed
five Operational Taxonomic Units (OTUs). DNA based identification of the
rest puffer species of Bangladesh with multiple sequences and
phylogenetic relationship remains to be established.