Genetic Approaches for Studying Myiasis-causing Flies: Molecular Markers and Mitochondrial Genomics

Abstract

"Myiasis-causing flies" is a generic term that includes species from numerous dipteran families, mainly Calliphoridae and Oestridae, of which blowflies, screwworm flies and botflies are among the most important. This group of flies is characterized by the ability of their larvae to develop in animal flesh. When the host is a live vertebrate, such parasitism by dipterous larvae is known as primary myiasis. Myiasis-causing flies can be classified as saprophagous (free-living species), facultative or obligate parasites. Many of these flies are of great medical and veterinary importance in Brazil because of their role as key livestock insect-pests and vectors of pathogens, in addition to being considered important legal evidence in forensic entomology. The characterization of myiasis-causing flies using molecular markers to study mtDNA (by RFLP) and nuclear DNA (by RAPD and microsatellite) has been used to identify the evolutionary mechanisms responsible for specific patterns of genetic variability. These approaches have been successfully used to analyze the population structures of the New World screwworm fly Cochliomyia hominivorax and the botfly Dermatobia hominis. In this review, various aspects of the organization, evolution and potential applications of the mitochondrial genome of myiasis-causing flies in Brazil, and the analysis of nuclear markers in genetic studies of populations, are discussed.

Offspring genetic structure reveals mating and nest infestation behaviour of an invasive parasitic fly (Philornis downsi) of Galápagos birds

“…An increased understanding of the reproductive behaviour of invasive insect parasites is central to the study of their population dynamics, life-history evolution and genetic structure, and may lead to more effective management strategies (Hendrichs et al 2002;Chevillon et al 2007;Song et al 2007). Genetic studies of parasitic, myiasis-causing flies have focused primarily on species of agricultural relevance, or have been mainly concerned with taxonomy and phylogenetics (Otranto and Stevens 2002;Azeredo-Espin and Lessinger 2006). Molecular genetic data on the reproductive biology and behaviour of myiasis-causing flies of birds (e.g.…”

Sequence and analysis of the mitochondrial DNA control region in the sugarcane borer Diatraea saccharalis (Lepidoptera: Crambidae)

“…The other variations were composed by the nucleotides deletions/insertions, and also in the number and length of the detected conserved regions as described elsewhere ( Fig. 2, underline; review in Azeredo-Espin and Lessinger, 2006). The control region of D. saccharalis presented one conserved block of long polythymidine stretch (17 nucleotides; Fig.…”

“…The presence of a potential origin of replication or regulatory elements, long poly-A and poly-T stretches, fast-evolving primary sequences and structurally instable elements, such as the multiple repeats and sequences able to form the secondary structures, may increase the technical and methodological difficulties related to access the mtDNA CR sequence data (AzeredoEspin and Lessinger, 2006). The amplification and sequencing using the primers developed for B. mori were functional and efficient to amplify the control region of the D. saccharalis (Fig.…”

Human Myiasis

“…Light microscopy and electro micrographic studies can confirm the identification and stage of larvae based on the presence of papillae, arrangement of anterior and posterior spiracles. Culture of larval forms to their adult forms is another method in identification [34,35].…”