Advances in the Study of Blastocystis spp. in Mexico: Prevalence, Genetic Diversity, Clinical Association and Their Possible Role in the Human Intestine

Blastocystis spp. has a worldwide distribution, and it has been associated with gastrointestinal symptomatology; however, its role in health or disease remains unclear. Subtype 3 is the most frequently reported subtype in different populations, with a high haplotype diversity. The recent diversity of this protist may be related to the migration of the human population. The ST3 haplotype network shows that haplotype 1 is ancestor from which the other haplotypes are derived. In the studied community (Xoxocotla, Morelos), a direct association exists between the presence of Blastocystis spp. and the changes in the bacterial and eukaryotic intestinal microbiota in the absence of gastrointestinal or inflammatory diseases, indicating that Blastocystis ST3 favors the diversity and richness of bacterial populations and decrease the inflammatory processes. Thus, there is important evidence that suggests that Blastocystis spp. plays an important role as a mutualist in the regulation of the inflammatory response in the studied healthy individuals.