Five big charismatic cats: Panthera leo (lion), Panthera tigris (tiger), Panthera onca (jaguar), Panthera pardus (leopard) and Uncia uncia (snow leopard) have been placed taxonomically in Pantherinae subfamily. They have been drawing attention of biologists due to important ecological roles . Consequently, extensive information is available on their natural history, morphology, behaviour, reproduction, evolutionary history and population genetic structure, which provides a rich basis for interpreting genetic data . The information is still not adequate to overcome their highly threatened status. Hence, molecular study is vital to further explore the genetic information which can be helpful for conservation.
Panthera leo has two geographically isolated populations; Panthera leo leo (African lion), and Panthera leo persica (Asiatic lion) . The Asiatic lion population is accorded endangered species status under the Indian Wildlife Protection Act, consisting only 411 wild animals . This population exist in and around Gir forest in the southwest part of Saurashtra region in the State of Gujarat, India. Presence of geographically confined single population having its origin from small nucleus group and constituting single gene pool, raises concerns about genetic diversity in Asiatic lion population. Morphological and molecular approaches like allozyme study  microsatellite analysis , protein markers and mitochondrial 12S gene  have been used to unveil the evolutionary history of this species. Earlier efforts have been made to undertake the population study of Panthera leo persica (NCBI Taxonomy ID: 83386) and other allied species  to establish phylogenetic status. However, it has been found to be perplexing .
For the last decade, mitochondrial DNA has been one of the most commonly used molecular marker in vertebrates for studying phylogeny and evolutionary relationships  among closely related species and subspecies . It can reveal evolutionary relatedness and elucidate large numbers of genome-level characteristics, such as relative arrangements of genes . It also has a great importance for the molecular identification of species. Cytochrome b and Cytochrome oxidase subunit I  are mitochondrial genes widely used for molecular identification of animals. Further, key mitochondrial features - a lack of recombination, essentially maternal inheritance, high evolutionary rate, compact size, and conserved gene order , have led to its wide spread use.
Earlier, phylogenetic relationship of the genus Panthera was studied using morphological, biochemical as well as molecular characters but it is still debatable and troublesome because of large disparities between these studies. The difficulty in resolving their phylogenetic relationships is a result of (i) a poor fossil record, (ii) recent and rapid radiation during the Pliocene, (iii) individual speciation events occurring within less than 1 million years (iv) probable introgression between lineages following their divergence . Phylogenetic relationship and position of Panthera leo, amongst the genus Panthera, has some knowledge gaps. The present study aims to provide some insights through the complete mitogenome of the Asiatic lion.