Mitochondrial PCR-RFLP assay to distinguish Triatoma brasiliensis macromelasoma from Triatoma brasiliensis brasiliensis subspecies (Hemiptera: Reduviidae)

• Grant number: 13/25708-6
• Support Opportunities: Regular Research Grants - Publications - Scientific article
• Start date: February 01, 2014
• End date: July 31, 2014
• Field of knowledge: Biological Sciences - Parasitology - Entomology and Malacology of Parasites and Vectors
• Principal Investigator: Mauro Toledo Marrelli
• Grantee: Mauro Toledo Marrelli
• Host Institution: Faculdade de Saúde Pública (FSP). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

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 and T. melanica), and each taxon displaying distinct ecological behavior. In order to evaluate the genetic relationships among nine T. brasiliensis s.l. populations from northeastern Brazil, we analyzed their mitochondrial cytochrome c oxidase subunit 1 sequences and suggested a PCR-RFLP assay to distinguish between T. brasiliensis macromelasoma and T. brasiliensis brasiliensis subspecies. All the specimens were morphologically identified as T. brasiliensis 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 subspecies T.b. macromelasoma. The second clade grouped T. brasiliensis brasiliensis populations. Restriction endonuclease sites were observed in the sequences and used in PCR-RFLP assays, producing distinct fingerprints for T. brasiliensis macromelasoma and T. brasiliensis brasiliensis populations. The results suggest that these are different species and that gene flow occurs only among T. brasiliensis brasiliensis populations, possibly associated with human activity in the area. (AU)