Columbia University scientists have used microarray analysis to study the effects of epigenetic influences and gene expression patterns on behavioral variability. Using genetically identical mice, their work, published in PLoS ONE this week, shows that variability in large-scale organization of gene expression levels in the hippocampus, rather than differences in the expression levels of specific genes, is associated with individual differences in behavior in the mice.
Also in PLoS ONE, researchers at Harvard used transcriptome analysis to study the aging brain. Comparing age-related gene expression changes in the cortex of humans, rhesus macaques, and mice on a genome-wide scale, they found that humans and rhesus macaques have a "dramatic increase" in age-dependent repression of neuronal genes and that many of these are associated with synaptic function. "Notably, genes associated with GABA-ergic inhibitory function are robustly age-downregulated in humans but not in mice at the level of both mRNA and protein," they write.
Scientists at the Netherlands Cancer Institute have uncovered a "major technical bias that hampers the identification of active microRNAs from mRNA expression profiles." To be able to identify regulatory elements from integrated expression and 3'-UTR sequences, they developed visualization and normalization methods to detect and remove 3'-UTR AU content in order to enhance the detection of active miRNAs. Their work was published last week in PLoS Computational Biology.
And finally, an essay in PLoS Medicine claims that the regular ebb and flow of commodity value doesn't really apply to scientific publication. "The 'winner's curse,' a more general statement of publication bias, suggests that the small proportion of results chosen for publication are unrepresentative of scientists' repeated samplings of the real world," they write. To change this flawed system, they suggest, among other things, publish everything in digital format and get rid of the bias toward publishing positive, over negative, results. And here's one we especially like: "Offer disincentives to herding and incentives for truly independent, novel, or heuristic scientific work."