The Broad Institute's Alexander Meissner and his colleagues report in a paper published online in advance in Nature this week on what they call "a unique regulatory phase of DNA methylation in the early mammalian embryo." Meissner et al. show that the mouse oocyte "contributes a unique set of differentially methylated regions — including many CpG island promoters — that are maintained in the early embryo but are lost upon specification and absent from somatic cells," and further provide a "genome-scale, base-resolution timeline of DNA methylation in the pre-specified embryo."
In an editorial appearing in this week's issue, the Nature staff says that "there are too many careless mistakes creeping into scientific papers." Nature says that PIs ought to be responsible for all of the data that comes out of their labs, journal editors ought to "offer online commenting, so that alert readers can point out errors," and that, more broadly, "there should also be increased scope to publish fuller results from an experiment and subsequent negative or positive corroborations."
Over in Nature Biotechnology, researchers at the University of Washington and at the University of Alabama at Birmingham "demonstrate the ability to resolve changes in current that correspond to a known DNA sequence by combining the high sensitivity of a mutated form of the protein pore Mycobacterium smegmatis porin A with phi29 DNA polymerase, which controls the rate of DNA translocation through the pore." Our sister publication In Sequence has more on the team's nanopore sequencing approach.