In PLOS Genetics, researchers from Duke University, the University of Copenhagen, and elsewhere search for host genetic variants contributing to severe, complicated forms of Staphylococcus aureus bacteremia. Using exome sequencing, the team profiled samples from 84 complicated and 84 uncomplicated S. aureus bacteremia cases, matched by patient features such as age and sex and by S. aureus bacterial clonal complex involved. When they assessed the most promising genes in a validation analysis in another 240 patients and considered blood array-based expression data for dozens of cases, the investigators saw a missense variant in the GLS2 gene with significant ties to complicated S. aureus bacteremia.
A Vassar College-led team takes a look at population genetic patterns in more than adult, female Guinea worms from Chad, Ethiopia, Mali, and South Sudan for a paper in PLOS Neglected Tropical Diseases. Based on information at nearly 23 nuclear microsatellite sites and variants across four mitochondrial gene sequences, the researchers saw enhanced genetic diversity in the Guinea worms from Chad, where the parasite re-emerged in 2010. For example, population structure varied geographically in the Guinea worms, while remaining genetically similar across host species, the authors note. And, they say, "the epidemiological evidence suggest that transmission in the Chadian context is currently being maintained by canine hosts."
Lung cancer samples from a small set of patients in China contain thousands of differentially methylated regions coinciding with dozens of genes showing altered expression, researchers from China and the US report in PLOS One. The researchers did array-based expression profiling on 10 paired lung cancer and non-cancerous lung tissues, using a methylated DNA immunoprecipitation and microarray (MeDIP-chip) method to profile DNA methylation. Together, the approaches uncovered nearly 5,800 hypermethylated regions and more than 1,100 regions with lower-than-usual methylation in the lung cancer samples — methylation shifts that appeared to correspond to decreased expression for 38 gene and increased expression for seven other genes.