Mitochondrial PCR-RFLP Assay to DistinguishTriatoma brasiliensis macromelasomafromTriatoma brasiliensis brasiliensisSubspecies (Hemiptera: Reduviidae)
Triatoma brasiliensis sensu lato(s.l.), the main vector of Chagas disease in northeastern Brazil, is a species complex comprising four species, one with two subspecies (T. brasiliensis brasiliensis,T. brasiliensis macromelasoma,T. juazeirensis,T. sherlocki, andT. melanica), and each taxon displaying distinct ecological requirements. In order to evaluate the genetic relationships among nineT. brasiliensiss.l. populations from northeastern Brazil, we analyzed their mitochondrial cytochrome c oxidase subunit 1 sequences and suggested a PCR-RFLP assay to distinguish betweenT. b. macromelasomaandT. b. brasiliensissubspecies. All the specimens were morphologically identified asT. b. brasiliensis. The resulting phylogenies identified two major clades that are congruent with the geographical populations studied. Based on collection sites and in accordance with type-location, one clade was identified as the subspeciesT. b. macromelasoma.The second clade groupedT. b. brasiliensispopulations. Restriction endonuclease sites were observed in the sequences and used in PCR-RFLP assays, producing distinct fingerprints forT. b. macromelasomaandT. b. brasiliensispopulations. The results suggest that these are different species and that gene flow occurs only amongT. b. brasiliensispopulations, possibly associated with human activity in the area.