In PLOS Genetics, Duke University's David Goldstein and colleagues from the US and Australia present a scheme for interpreting information in personal genomes. With the help of 6,500 exomes sequenced through the National Heart, Lung, and Blood Institute's Exome Sequencing Project, the group came up with a so-called intolerance scoring system that quantifies the functional variation found in genes relative to their typical level of tolerance to such variability. For instance, the intolerance ranking strategy found far less wiggle room for variants in Mendelian disease genes, study authors note, and revealed a range of patterns in other disease culprits depending on the type of condition involved.
Researchers from the Universities of Exeter and Newcastle describe findings from a genome sequencing study of the fish-infecting microsporidean parasite Spraguea lophii in another PLOS Genetics study. By sequencing and assembling nearly 5 million bases of the S. lophii genome, the team determined that the parasite has lost many protein families found in other eukaryotes, consistent with its obligate intracellular lifestyle. Even so, the study's authors also saw expansions to certain protein families. Together with findings from their comparative genomics, RNA sequencing, and proteomic experiments, such genome sequence patterns provided clues about how S. lophii manages to take hold in their hosts, eventually turning some tissues in the fish nervous system into puffy spore-producing clusters called xenomas.
Periodic rabies outbreaks in Trinidadian livestock can be traced back to a bat rabies virus resembling those causing disease in vampire bats, according a PLOS Neglected Tropical Diseases study. Researchers from Trinidad and Tobago, the US, and the UK used molecular and phylogenetic analyses to identify two main lineages within this bat virus group. In addition to finding evidence for at least three different rabies virus introductions to the Caribbean island from the mainland, they delved into the evolution of the broader history of the vampire bat rabies-related viruses, which appear to have expanded in Mexico and Brazil in particular.