Research Articles

Polymerase chain reaction-based identification and genotyping of Anopheles mosquitoes with a 96-pin bacterial replicator

A simple method for rapid identification of large numbers of Anopheles mosquitoes was developed based on polymerase chain reaction (PCR) amplification of the rDNA intergenic spacer and internal transcribed spacer 2. By means of previously described primers for the Anopheles gambiae and An. quadrimaculatus species complexes, rDNA was amplified simultaneously from 96 whole mosquitoes or parts. No homogenization or individual DNA preparation was necessary, and transfer of 96 samples to PCR reactions was performed simultaneously with a bacterial replicator. Control reactions indicate that the level of cross-contamination is negligible, and false-negative findings are rare. The method was tested on larvae, pupae, adult heads, whole adult males and females, and single tarsi. All parts except tarsi provided satisfactory template. Fresh, ethanol-preserved, dried, and frozen adults were also tested with similar results. The method was also tested for amplification of a single-copy gene, white. Results were generally positive, although some false-negative findings were observed. This method allows rapid analysis of large numbers of mosquitoes without robotic equipment and should enable rapid and extensive PCR analysis of field-collected samples and laboratory specimens.