Molecular identification of Aedes aegypti mosquitoes from Pilani region of Rajasthan, India.

BACKGROUND & OBJECTIVES: Aedes aegypti is the most important vector of dengue virus infection in humans worldwide. Accurate identification and colonization are the essential requirements to understand vector biology as well as its diseases transmission potential. In this study, we have used molecular approaches for the identification of Ae. aegypti mosquitoes that were collected from the Pilani region of Rajasthan, India Methods: Field collected mosquito larvae were colonized under laboratory conditions. Conserved genetic markers, ITS-2 and mtCOI were used for amplification through species-specific primers to identify the mosquito species/ strain. Sequencing result of this strain was phylogenetically compared with other global strains through MEGA software.

RESULTS

A comprehensive multiple sequence alignment and phylogenetic analysis revealed that COI gene of Ae. aegypti has extremely low genetic variability with one of the Indian isolate from Thirumala, Andhra Pradesh region (GenBank: HM807262.1). However, in context of different geographical locations, it indicated close similarity with Thailand's strain and high variability when compared with Madagascar strain. On the other hand, ITS-2 illustrated highest identity with Ae. aegypti of Saudi Arabia (GenBank: JX423807.1) whereas, high divergence was observed from Mayotte, France strain (GenBank: KF135506).

INTERPRETATION & CONCLUSION: The findings suggest that this isolate from Rajasthan is similar to other Asian continent strains possibly due to the same origin. Understanding the vectorial capacity of these geographically distributed mosquito strains will enhance our knowledge to improve existing vector surveillance and control programme.