The main aim of this study was to perform DNA barcoding of Portunus pelagicus from Mumbai region using DNA markers specifically used as DNA barcodes. In this study, we have performed molecular taxonomy of Portunus pelagicus based on gene loci namely Cytochrome Oxidase Subunit I, 18S rRNA and Histone H3. In the beginning, genomic DNA was isolated using CTAB method. Polymerase Chain Reaction of COI, Histone H3 and 18S rRNA genes were performed and sequenced. The DNA sequences of the respective genes were analysed using Finch TV version 1.4 and BLAST was performed to understand the sequence similarity. FASTA sequence of all the three barcodes of Portunus pelagicus were compared with the FASTA sequence of other related crab species using Multialin tool and Clustal Omega. With the help of Multialin tool, it was easier to study the evolutionary relationship between the sequences for the respective gene loci. Clustal Omega was used to evaluate the phylogenetic relationships between Portunus pelagicus and other crabs from the same family. Thus, in this study we propose that the three DNA barcodes viz; COI, Histone H3 and 18S rRNA can be used to discriminate between crab species by comparative evaluation using phylogenetic tree.
