Egli, D. et al. Preprint at http://www.biorxiv.org/content/early/2017/08/28/181255 (2017). A critique of: doi:10.1038/nature.2017.22382 (dated Aug 2) Here is the more news science version of the CRISPR study: https://www.nature.com/news/crispr-fixes-disease-gene-in-viable-human-embryos-1.22382 And news science version for the criticism: http://www.nature.com/news/doubts-r...embryos-1.22547?WT.mc_id=SFB_NNEWS_1508_RHBox This is how Science works. You perform experiments, publish your results, then you may have to answer criticism. This is a good thing. In this case the original claim was to remove a deleterious gene using CRISPR technology. Not completely correct say a second group of researchers. The criticism deals with the fact that the created embyos had two normal gene copies, but no explainable way (in terms of what was originally reported) for one of those copies to be in the embryo. (Read the the two news articles. In order for me to get everything correct I'd have to plagiarize a lot of text from the articles.) Maybe @Ygggdrasil can do that without plagiarzing. The important concept is that Science does attempt to self correct: Not always, and not perfectly because humans are involved.