In PLOS Genetics, researchers from the US, Switzerland, and Germany describe a deletion in the rho guanine nucleotide exchange factor 10 gene ARHGEF10 that can cause an inherited, juvenile-onset polyneuropathy and muscle atrophy condition in the Leonberger dog breed that resembles Charcot-Marie-Tooth disease. Using canine SNP-based genotyping data on 52 Leonberger dogs with polyneuropathy and 41 without, the team mapped the disease back to a chromosome 16 region containing ARHGEF10. Targeted sequencing uncovered an ARHGEF10 alteration that shifted its splicing patterns and lopped off part of the resulting protein — a polyneuropathy-associated change that was also detected in follow-up experiments involving Saint Bernards with a similar malady.
A University of California, San Francisco-led team took a look at human liver regulatory elements involved in drug response and reactions for another PLOS Genetics study. The researchers tested primary human hepatocytes that had or had not been treated with an antibiotic called rifampin, using RNA sequencing and chromatin immunoprecipitation sequencing studies targeting a specific receptor and regulatory marks. Together with additional assays and genomic tests, they tracked down almost 1,300 regions in the genome that seem to mediate xenobiotic metabolism and defined enhancer variations that alter drug response activity.
A paper in PLOS Neglected Tropical Diseases by Brazilian researchers describes efforts to establish RNA interference-based genomics tools for the pathogenic fungus Paracoccidioides brasiliensis, using genome sequences generated through the Broad Institute's Fungal Genome Initiative and molecular techniques involving Agrobacterium tumefaciens-assisted yeast transformation experiments. "[W]e have developed appropriate molecular tools and straightforward techniques to streamline the generation of stable loss-of-function phenotypes for the human-pathogen Paracoccidioides brasiliensis," the study's authors explain, "which is phylogenetically related to Blastomyces dermatitidis, Coccidioides immitis, and Histoplasma capsulatum."