Using ancient bacterial DNA sequences obtained from human tooth samples found in Europe and Asia that stretched back as far as 5,000 years, a University of Copenhagen-led team explores the origins of the plague-causing pathogen Yersinia pestis. The team tracked down seven tooth samples containing Y. pestis-like sequences when it tested samples from more than 100 Bronze Age individuals. Genome sequence data from these samples placed the most recent common ancestor of the plague pathogen at almost 5,800 years ago, though a plasmid-borne gene associated with Y. pestis survival in fleas appeared later. GenomeWeb has more on the study, here.
A team from Brazil, Sweden, and the US reports on a potential modifier for Duchenne muscular dystrophy that it detected in dog models of the disease. The researchers did genome-wide mapping, genome sequencing, and transcriptomic analyses on two related Golden retrievers that carried Duchenne muscular dystrophy-causing mutations in the dystrophin gene but had only mild symptoms and did not show typical muscle function loss. The data revealed an uptick in expression of a Notch signaling pathway regulatory gene called Jagged1 in these so-called muscular dystrophy 'escaper' dogs, hinting at the possibility of targeting gene in human forms of the disease.
University of Washington researchers describe the massively parallel reporter assays they used to improve sequence determinant models for alternative splicing. Using libraries of synthetic mini-genes containing barcoded mini-genes with degenerate sub-sequences and variable introns in a human cell line, the team did RNA sequencing-based profiling on almost two million alternatively spliced mini-gene products. "The massive size of these training data allowed us to improve upon current models of splicing, as well as to gain new mechanistic insights," authors of the analysis note, explaining that the study offers insights into splice site selection and sequences associated with exon inclusion.