In PLOS Genetics, researchers from Singapore and elsewhere describe findings from a comparative genomic study of Malassezia, a genera of fungus found in the human skin mycobiome, including representatives associated with certain skin conditions. By sequencing and comparing the genomes of 14 Malassezia species to one another and to other fungi, the team narrowed in on signatures of selection that offer clues to lifestyle adaptations in Malassezia, as well as genetic variants, gene gains, and gene losses that distinguish them from other fungi. "[O]ur study provides a unique genomic resource for understanding Malassezia niche-specificity and potential virulence," the study's authors note, "as well as their abundance and distribution in the environment and on human skin."
A team from the University of Chicago and the Saint Justine Hospital Research Center in Montreal searched the human host genome for associations with gut microbiome features in a study published in PLOS One. The researchers combined genotyping profiles from dozens of Hutterite individuals with 16S ribosomal RNA sequencing data that was used to determine the gut microbes found in their fecal samples during summer and winter. In the process, they found SNPs that coincided with levels of eight bacterial taxa in the individuals' gut microbial communities, including a variant neighboring an body mass index-associated gene called PLD1 with ties to levels of a microbial genera that's been independently implicated in obesity.
Investigators in Canada and the Netherlands explore the gene expression effects that cholesterol-reducing statin drugs have on human lung tissue in another PLOS One paper. Using a custom Affymetrix array, the team tracked gene expression in lung samples from more than 400 individuals treated for cancer or other conditions by transplantion or lung resection. Roughly one-third of the individuals took statins prior to surgery — a treatment associated with altered expression of 21 genes in the discovery set. After replication in two replication sets involving hundreds more individuals, the study's authors were left with a dozen genes showing enhanced expression in the lung tissue of statin users. The set did not include inflammatory or fibrotic genes, they note, suggesting "the improved health outcomes and survival observed in statin users with chronic lung diseases do not seem to be mediated through direct regulation of gene expression in the lung."