DNA barcoding complementing morphological taxonomic identification of mosquitoes in peninsular Malaysia

A Noor Afizah, MM Torno, J Nur Jannah, AH Azahari, M Khairul Asuad, WA Nazni, HL Lee

Abstract

Morphology-based mosquito identification is a gold standard, which is inexpensive and requires minimal tools and/or equipment. Nonetheless, it re-quires a high level of expertise and misdiagnosis is common. In addition, quality of samples is not always sufficient for identification at the species level. Hence, we explored the potential use of a gene-based DNA barcoding utilizing cytochrome c oxidase subunit I (COI) gene for mosquito identification. Ninety mosquito samples belonging to 13 species of 5 genera pre-identified using taxonomic keys were subjected to PCR and sequencing of COI gene. Specific anatomical parts, such as body (thorax and abdomen), leg and wing were also subjected to PCR to test for the utility of such parts for DNA barcoding, obtaining varying success with wings being the least successful. BLAST search showed sequences were 94-99% in agreement with morphological identification. Neighbor-joining tree analysis of COI gene fragment sequences allowed determination of phylogenetic relationships and reliable computation of divergence between taxa. Our findings suggested that COI-based DNA barcoding is a useful tool to complement taxonomy-based identification of mosquito species.