Genetic Diversity of Dioctophyma renale in Northeast Argentina and Southern Brazil

ARCE, L. F.; GIORELLO, N.; ARRABAL, J.P; MALDONADO, L.; BUTTI, M.; FRANCHINI, G.; BELDOMENICO, P.; KAMENETZKY, L.

Encuentro; Molecular Parasitology Meeting XXXI; 2020

Dioctophyma renale is a parasitic nematode that infects thekidney of mammals (mainly Order Carnivora). It can grow and exceed the meter,completely destroying the kidney. Therefore, its infection is stronglydebilitating and even fatal. Numerous cases in veterinary clinics were observedon the Argentine coast. A prevalence in domestic dogs of 36.3% was determinedon the coasts of Río de la Plata. There are also reports of dioctophymosis indogs from the riverside region of the Chaco and Formosa provinces. In addition,there are reports of infections by this same parasite in wild carnivoresincluding, among themCrysocyonbrachiurus; making this parasite a possiblethreat to the conservation of some endangered species.From genome Project (developed by our laboratory), a mitochondrialgenome of D. renale was assembled and three molecular markers ofdifferent sizes from cytochrome oxidase I (COX1) gene were designed.46 adultsof Dioctophyma renale were collected from interventions in veterinaryclinics and from necropsies of wild fauna in different locations innortheastern Argentina and southern Brazil. DNA was extracted from each sampleand those markers were amplified by PCR. The amplified products were typed bySNPs analysis and phylogenetically analyzed with sequences available in theGenBank. They came from Japan, Peru, Canada and Iran.Local genetic variants of South American was observed, without geographicdifferentiation between the localities of Brazil and Argentina, but a greatseparation with respect to the sequences of other regions of the world. Nor wasany structuring by host species observed. The phylogenies constructed with thedifferent markers are consistent with each other. Although the largest markersshowed more diversity, in all cases clustering was consistent with the observedin the smallest marker. Molecular evidence suggests that Dioctophyma renalepopulations were in South America long enough to develop local geneticvariants. They could have come from the north of the continent and dispersedbetween Brazil and Argentina on more than one occasion. Finally, the samevariants can infect and be transmitted between domestic and wild mammals in thestudied region.