In Science this week, an international team of researchers publishes the results of one of the largest scientific reproducibility investigations ever, which sought to replicate a hundred recently published psychology studied. The investigators report that while they were able to repeat almost all of the studies, they were only able to replicate the findings in less than half. The study's authors caution that their failure to reproduce does not necessarily indicate that the original study was flawed, but highlights the challenges of reproducing scientific findings and the importance of developing new methods to do so.
Also in Science, a team led by Rice University researchers describes the creation of a synthetic microbial consortium they view as a step forward toward engineering synthetic tissues and organs of multiple cell types. The consortium consists of two distinct cell types — an "activator" strain and a "repressor" strain, which produce two orthogonal cell-signaling molecules that regulate gene expression within a synthetic circuit spanning both strains. The two strains generate emergent, population-level oscillations only when cultured together and establish a platform for testing the relation between population-level dynamics and genetic-level regulation.
And in Science Translational Medicine, a group of US and UK scientists report on the development of a new method that uses DNA to predict relapses in early-stage breast cancer patients. The investigators prospectively studied 55 women with the disease who had been treated with chemotherapy followed by surgery. Using digital PCR and massively parallel sequencing, they then tracked tumor-specific mutations in blood samples taken regularly from the patients in the two years following their treatment. Circulating tumor DNA was able to accurately predict 12 of the 15 patients who relapsed eight month before it could be detected using conventional imaging. In some patients, the DNA analysis was also able to identify mutations involved in metastasis or drug resistance. GenomeWeb has more on this study here.