RESUMO
Blastocystis subtype 3 (ST3) is a parasitic protist found in the digestive tract of symptomatic and asymptomatic humans around the world. While this parasite exhibits a high prevalence in the human population, its true geographic distribution and global genetic diversity are still unknown. This gap in knowledge limits the understanding of the spread mechanisms, epidemiology, and impact that this parasite has on human populations. Herein, we provided new data on the geographical distribution and genetic diversity of Blastocystis ST3 from a rural human population in Mexico. To do so, we collected and targeted the SSU-rDNA region in fecal samples from this population and further compared its genetic diversity and structure with that previously observed in populations of Blastocystis ST3 from other regions of the planet. Our analyses reveled that diversity of Blastocystis ST3 showed a high haplotype diversity and genetic structure to the world level; however, they were low in the Morelos population. The haplotype network revealed a common widespread haplotype from which the others were generated recently. Finally, our results suggested a recent expansion of the diversity of Blastocystis ST3 worldwide.
Assuntos
Infecções por Blastocystis/genética , Blastocystis/genética , DNA Ribossômico/genética , Variação Genética , Adolescente , Adulto , Blastocystis/patogenicidade , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Criança , Pré-Escolar , DNA de Protozoário , Fezes/parasitologia , Feminino , Trato Gastrointestinal/parasitologia , Trato Gastrointestinal/patologia , Haplótipos/genética , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Filogenia , População Rural , Adulto JovemRESUMO
Blastocystis spp. es el protista intracelular que se detecta con mayor frecuencia en muestras de materia fecal humana; las tasas de infección pueden superar el 20% en países en vías de desarrollo. El hallazgo de este parásito en heces de diversas especies animales sugiere su potencial zoonótico. La relevancia clínica y el papel patógeno de Blastocystis spp. en el tracto intestinal son inciertos. Varias son las publicaciones que lo reconocen como agente etiológico de desórdenes intestinales como diarrea, enfermedad inflamatoria intestinal y colitis ulcerosa, aunque la patogenicidad de este parásito no ha sido probada. Este amplio rango de respuestas a la infección podría estar relacionado con la diversidad genética de los aislamientos provenientes de hospedadores infectados.
Blastocystis spp. is the most common protozoan detected in human stool samples. In developing countries, infection rates are higher than 20%. The presence of this parasite in the feces of several host species suggests its zoonotic potential. The clinical relevance and the pathogenic role of Blastocystis spp. in the intestinal tract remain unclear. There are several clinical reports that recognize it as the etiologic agent of several intestinal disorders such as diarrhea, inflammatory bowel disease and ulcerative colitis, although the pathogenicity of this parasite has not been proved yet. This wide range of clinical manifestations could be related to the genetic diversity exhibited by this parasite.
Assuntos
Humanos , Infecções por Blastocystis , Blastocystis , Variação Genética , Infecções por Blastocystis/diagnóstico , Infecções por Blastocystis/genética , Infecções por Blastocystis/terapia , Blastocystis/isolamento & purificação , Diarreia , FezesRESUMO
Blastocystis spp. is the most common protozoan detected in human stool samples. In developing countries, infection rates are higher than 20%. The presence of this parasite in the feces of several host species suggests its zoonotic potential. The clinical relevance and the pathogenic role of Blastocystis spp. in the intestinal tract remain unclear. There are several clinical reports that recognize it as the etiologic agent of several intestinal disorders such as diarrhea, inflammatory bowel disease and ulcerative colitis, although the pathogenicity of this parasite has not been proved yet. This wide range of clinical manifestations could be related to the genetic diversity exhibited by this parasite.