RESUMO
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.
Assuntos
Doenças do Cão/parasitologia , Sarcoptes scabiei/genética , Escabiose/parasitologia , Alelos , Animais , Análise por Conglomerados , DNA/química , Impressões Digitais de DNA/veterinária , Repetições de Dinucleotídeos/genética , Reservatórios de Doenças , Doenças do Cão/epidemiologia , Cães , Eletroforese/veterinária , Variação Genética , Genótipo , Humanos , Marsupiais , Havaiano Nativo ou Outro Ilhéu do Pacífico , Northern Territory/epidemiologia , Ohio/epidemiologia , Panamá/epidemiologia , Reação em Cadeia da Polimerase/veterinária , Coelhos , Escabiose/epidemiologia , Pele/parasitologia , Vitória/epidemiologia , ZoonosesRESUMO
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.
Assuntos
Proteínas Sanguíneas/genética , Deleção Cromossômica , Plasmodium falciparum/genética , Proteínas de Protozoários , Animais , Proteínas Sanguíneas/fisiologia , Adesão Celular/genética , Cromossomos Artificiais de Levedura , Eletroforese em Gel de Campo Pulsado , Genes de Protozoários , Parasitologia/métodos , Peptídeos/genética , Peptídeos/fisiologia , Plasmodium falciparum/fisiologia , Reprodução , Seleção Genética , Células Tumorais CultivadasRESUMO
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