In this week's Science, an international research team presents a study combining field and laboratory experiments to identify the ecological and molecular mechanisms underlying trait adaptation in wild mice. The scientists directly estimate natural selection on pigmentation traits and an underlying pigment locus by using experimental enclosures of mice on different soil colors. They also use next-generation sequencing and other techniques to show how a mutation in the locus that is associated with survival causes lighter coat color through changes in its protein-binding properties. The findings, they write, "demonstrate how a sequence variant alters phenotype and then reveal the ensuing ecological consequences that drive changes in population allele frequency, thereby illuminating the process of evolution by natural selection."
And in Science Translational Medicine, a group of Israeli scientists discuss advances in microbiome research and progress toward using these discoveries in therapeutic development. They look at the primary strategies for modulating the microbiome — dietary interventions, probiotics, bacterial metabolites, and fecal transplantation — and highlight the need for targeted approaches that only eliminate harmful bacteria. The authors say "stringent testing" in the form of randomized placebo-controlled clinical trials, as well as accommodations by regulatory agencies, will be necessary for the clinical translation of microbiome science. "Uniform, rigorous, and unbiased experimental and regulatory approaches, similar to the careful and stringent testing and approval processes practiced in other human interventions, will allow the safe and efficacious long-term integration of microbiome-based therapies into the treatment of a variety of different diseases," they conclude.