Intragenomic heterogeneity of rDNA internal transcribed spacer 2 in Anopheles messeae (Diptera: Culicidae)

Because Anopheles messeae Falleroni (Diptera: Culicidae) is one of the main vectors of malaria in Russia, studying its genetic markers is important for reliable identification of this species. This species is distributed nearly throughout the Palearctic region, and it exhibits high genetic variability. We investigated polymorphism of the rDNA internal transcribed spacer (ITS) 2 of An. messeae in various regions of Russia, and we found intragenomic heterogeneity of ITS2 copies verified by chromatograms, polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis, and cloning PCR products. In total, we found nine different ITS2 variants. ITS2 variants that were considered specific to An. messeae and Anopheles daciae Linton, Nicolescu & Harbach were simultaneously present in one individual. These findings improve methods of species identification of An. messeae, and they do not support the species status of An. daciae.