In the early, online edition of the Proceedings of the National Academy of Sciences, a team from the Forsyth Institute, the Marine Biological Laboratory at Woods Hole, and Harvard's School of Dental Medicine set out to map the mouth microbiome's biogeography. By bringing metagenomic sequencing clues together with spectral imaging fluorescent in situ hybridization, the researchers identified highly ordered consortia in human dental plaque samples, containing bacterial from multiple genera that were organized in ways suspected of fitting with the function and interactions of each. "The spatial structure of the consortium reveals unanticipated interactions and provides a framework for understanding the organization, metabolism, and systems biology of the microbiome and, ultimately, its effect on the health of the human host," the authors say.
Researchers from the Netherlands report on findings from a three-dimensional spatial gene expression analysis of steroid receptor pathways and activity in the mouse brain for another PNAS paper. Using available data from the Allen Brain Atlas, as well as new expression data for a dozen mouse brain regions, the team characterized co-expression for various steroid receptors in different parts of the brain. The study's authors note that the resulting data "constitute a rich repository for the research community to support further new insights in neuroendocrine relationships and to develop novel ways to manipulate brain activity in research or clinical settings."
A group based in West Bengal, India explores ancestry components found in present-day populations in India. Using genome-wide SNP data for 18 diverse populations on mainland India and two populations on the Andaman and Nicobar Islands, the researchers identified four main ancestry components in the genomes of individuals in mainland India: the previously described Ancestral North Indian and Ancestral South Indian groups, along with Tibeto-Burman and Austro-Asiatic ancestral groups. Their results also highlighted a fifth ancestry group amongst individuals from the Andaman archipelago, where populations tended to be differentiated from those on the mainland. GenomeWeb has more on the study, here.