Submitted to: American Society of Parasitologists
Publication Type: Abstract Only
Publication Acceptance Date: 4/28/2009
Publication Date: 8/14/2009
Citation: Santin, M., Gomez-Munoz, M., Fayer, R. 2009. Development of a new PCR protocol to detect and subtype Blastocystis spp. from humans and animals. 84th American Society of Parasitologists Meeting. p. 40
Technical Abstract: Blastocystis spp. has been found in several other species of vertebrates and it is one of the most prevalent parasites found in the feces of humans worldwide. Infection with Blastocystis in humans has been reported as asymptomatic, acute symptomatic, infection, and chronic symptomatic. The range of responses to infection with Blastocystis spp. could be related to the genetic diversity of morphologically indistinguishable specimens obtained from infected hosts. The former name Blastocystis hominis is now reported as Blastocystis spp. because it has become apparent that different species or subtypes exist but have not been fully characterized. Genetic diversity among Blastocystis spp. isolates has been studied by molecular biology approaches. Because Blastocystis spp. has been identified in feces from several animal species a potential zoonotic role has been proposed for organisms in this genus. In this study, a PCR and sequencing protocol was developed using primers that were complementary to conserved regions of published nucleotide SSU rDNA sequences of Blastocystis downloaded from GenBank from all Blastocystis subtypes. This PCR protocol that amplifies a fragment of SSU rDNA of around 500 bp was found to be highly sensitive compared with previously published primers. The SSU rDNA gene fragment amplified by this PCR contained high variable regions that allow phylogenetic analysis of Blastocystis. These primers were able to detect and subtype Blastocystis spp. isolated from naturally infected cattle, pigs, humans, primates, ostrich, and chicken. Application of this method can elucidate the complexity of this heterogeneous genus and its role in human or animal diseases as well as its zoonotic potential.