Identification and Molecular Characterization of Four New Blastocystis Subtypes Designated ST35-ST38

Abstract

Three recent studies of <i>Blastocystis</i> epidemiology in mammalian hosts identified four novel sequences that appeared to share <i>B. lapemi</i> as the most similar sequence. However, full-length <i>ssu</i> rRNA gene sequences were not available to confirm the validity of these new subtypes. In the present study, Nanopore MinION sequencing was used to obtain full-length reference sequences for each of the new subtypes. Additionally, phylogenetic analyses and pairwise distance comparisons were performed to confirm the validity of each of these new subtypes. We propose that the novel sequences described in this study should be assigned the subtype designations ST35-ST38. The full-length reference sequences of ST35-ST38 will assist in accurate sequence descriptions in future studies of <i>Blastocystis</i> epidemiology and subtype diversity.