Use of chitinase to facilitate detection of protozoan, helminth and single copy genes in squashed whole mosquitoes

Abstract The application of DNA probes to detect foreign DNA in whole arthropods has been limited by the inability of the probes to distinguish between small quantities of target DNA and the background signal generated by non-specific hybridization of mosquito material. We report that treatment of nitrocellulose filters upon which mosquitoes have been squashed with chitinase and proteinase K eliminates non-specific hybridization of DNA probes to mosquito components. Using this technique we have been able to detect a single larva of Brugia malayi , sporozoites of Plasmodium falciparum and Plasmodium berghei , and a single-copy gene in directly squashed vector mosquitoes. Use of this simple, rapid technique should facilitate the successful use of DNA probes in field studies.