RESUMEN
Overcrowding is a significant factor contributing to endemic infection with Sarcoptes scabiei in human and animal populations. However, since scabies mites from different host species are indistinguishable morphologically, it is unclear whether people can be infected from scabies-infested animals. Molecular fingerprinting was done using three S. scabiei-specific single locus hypervariable microsatellite markers, with a combined total of 70 known alleles. Multilocus analysis of 712 scabies mites from human and dog hosts in Ohio, Panama and Aboriginal communities in northern Australia now shows that genotypes of dog-derived and human-derived scabies cluster by host species rather than by geographic location. Because of the apparent genetic separation between human scabies and dog scabies, control programs for human scabies in endemic areas do not require resources directed against zoonotic infection from dogs.
Asunto(s)
Enfermedades de los Perros/parasitología , Sarcoptes scabiei/genética , Escabiosis/parasitología , Alelos , Animales , Análisis por Conglomerados , ADN/química , Dermatoglifia del ADN/veterinaria , Repeticiones de Dinucleótido/genética , Reservorios de Enfermedades , Enfermedades de los Perros/epidemiología , Perros , Electroforesis/veterinaria , Variación Genética , Genotipo , Humanos , Marsupiales , Nativos de Hawái y Otras Islas del Pacífico , Northern Territory/epidemiología , Ohio/epidemiología , Panamá/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Conejos , Escabiosis/epidemiología , Piel/parasitología , Victoria/epidemiología , ZoonosisRESUMEN
Many lines of Plasmodium falciparum undergo a deletion of the right end of chromosome 9 during in vitro culture accompanied by loss of cytoadherence and gametocytogenesis. Selection of cytoadherent cells from a mixed population co-selects for those with an undeleted chromosome 9 and the selected cells produce gametocytes. The deletion also results in loss of expression of PfEMP1, the putative cytoadherence ligand, suggesting that PfEMP1 or a regulatory gene controlling PfEMP1 expression and gametocytogenesis may be encoded in this region. We have isolated several markers for the deleted region and are currently using a YAC-P. falciparum library to investigate this region of the genome in detail.
Asunto(s)
Proteínas Sanguíneas/genética , Deleción Cromosómica , Plasmodium falciparum/genética , Proteínas Protozoarias , Animales , Proteínas Sanguíneas/fisiología , Adhesión Celular/genética , Cromosomas Artificiales de Levadura , Electroforesis en Gel de Campo Pulsado , Genes Protozoarios , Parasitología/métodos , Péptidos/genética , Péptidos/fisiología , Plasmodium falciparum/fisiología , Reproducción , Selección Genética , Células Tumorales CultivadasRESUMEN
Many lines of Plasmodium falciparum undrgo a deletion of the right end of chromosome 9 during in vitro culture accompanied by loss of cytoadherence and gametocytogenesis. Selection of cytoadherent cells from a mixed population co-selects for those with an undeleted chromosome 9 and selected cells produce gametocytes. The deletion also results in loss of expression of PfEMP1, the putative cytoadherence ligand, suggesting PfEMP1 or a regulatory gene controlling PfEMP1 expression and gametocytogenesis may be encoded in this region. We have isolated several markers for the deleted region and are currently using a YAC-P. falciparum library to investigate this region of the genome in detail