Mitochondrial 12S rRNA gene sequence analysis, a tool for species identification

Biodiversity is under threat worldwide. Many species of animals, birds and reptiles have experienced considerable decline in their populations within the past two centuries due to illegal trade, poaching and habitat destruction. The biodiversity in India is under threat due to growing wildlife crime. In this study a segment of mitochondrial 12S rRNA was used to develop an easy and standard protocol to identify a number of species from variety of samples. Polymerase chain reaction (PCR) was done after DNA extraction and quantification. PCR products were then sequenced bidirectionally and aligned to a database non reductant nucleotide sequence. It was then confirmed that the sequences aligned specifically to mitochondrial sequences from expected species of origin. Bioinformatics tools were then applied for phylogenetic and genetic diversity analysis. Result of this study showed that universal primer could amplify partial mitochondrial 12rRNA gene from all studied animals, birds and reptiles. Based on the sequences obtained, a Neighbour joining tree was constructed using K2P model. This molecular technique together with bioinformatics tools provides a reliable and fast method for species identification and taxonomic classification.