An international team led by investigators at the University of Michigan Medical School reports on its study of how germ-free mice "are unable to eradicate Citrobacter rodentium, a model for human infections." These results, the team says in a paper published online in advance this week, suggest that "pathogen colonization is controlled by bacterial virulence and through competition with metabolically related commensals."
Over in this week's issue, Cornell University's Alon Keinan and Andrew Clark characterize signatures of explosive growth in human populations "on the site frequency spectrum," with which they conclude "that the discrepancy in rare variant abundance across demographic modeling studies is mostly due to differences in sample size." Overall, Keinan and Clark say, "rapid recent growth increases the load of rare variants and is likely to play a role in the individual genetic burden of complex disease risk." As such, they add, "the extreme recent human population growth needs to be taken into consideration in studying the genetics of complex diseases and traits."
A team led by researchers at the National Institute of Information and Communications Technology in Kobe, Japan, shows that "the sme2 gene encodes a meiosis-specific non-coding RNA that mediates homologous recognition in the fission yeast Schizosaccharomyces pombe." Deletion of the sme2 sequence results in the elimination of robust pairing of homologous chromosomes, the researchers say, and thus they suggest that "RNA transcripts retained on the chromosome play an active role in recognition of homologous chromosomes for pairing."
Elsewhere in this week's issue, an international collaboration led by Jane Kaye from the University of Oxford presents ELSI 2.0, an initiative "designed to catalyze international collaboration in ELSI [ethical, legal, and social implications of] genomics and to enable those in the field to better assess the impact and dynamics of global genome research." The aim of this project "is to accelerate the translation of ELSI research findings into practice and policy," Kaye and her colleagues write in Science.