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<jats:title>DNA sequence and inherited gene silencing</jats:title> <jats:p> Cell fate decisions require a gene's transcriptional status, whether on or off, to be stably and heritably maintained over multiple cell generations. For silenced genes, heterochromatin domains are associated with specific histone posttranslational modifications, and these histone marks are maintained during DNA replication and chromosome duplication (see the Perspective by De and Kassis). Laprell <jats:italic>et al.</jats:italic> show that parental methylated histone H3 lysine 27 (H3K27) nucleosomes in <jats:italic>Drosophila</jats:italic> are inherited in daughter cells after replication and can repress transcription, but that they are not sufficient to propagate the mark. Trimethylation of newly incorporated nucleosomes requires recruitment of the methyltransferase Polycomb repressive complex 2 (PRC2) to neighboring cis-regulatory DNA elements. Coleman and Struhl demonstrate that H3K27 trimethylated nucleosomes play a causal role in transmitting epigenetic memory at a <jats:italic>Drosophila</jats:italic> HOX gene through anchoring of PRC2 at the Polycomb response element binding site. Wang and Moazed examine fission yeast and show that both sequence-dependent and chromodomain sequence-independent mechanisms are required for stable epigenetic inheritance of histone modifications and the epigenetic maintenance of silencing. These studies highlight the crucial role of DNA binding for heritable gene silencing during growth and development. </jats:p> <jats:p> <jats:italic>Science</jats:italic> , this issue p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6333" page="85" related-article-type="in-this-issue" vol="356" xlink:href="10.1126/science.aai8266">85</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6333" page="eaai8236" related-article-type="in-this-issue" vol="356" xlink:href="10.1126/science.aai8236">eaai8236</jats:related-article> , p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6333" page="88" related-article-type="in-this-issue" vol="356" xlink:href="10.1126/science.aaj2114">88</jats:related-article> ; see also p. <jats:related-article xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="doi" issue="6333" page="28" related-article-type="in-this-issue" vol="356" xlink:href="10.1126/science.aan1493">28</jats:related-article> </jats:p>

<jats:p> In Frank Capra's seasonal classic <jats:italic>It's a Wonderful Life</jats:italic> , the main character, George Bailey, wishes he had never been born and is then transported to a version of his world where all traces of his existence have been removed. This world is much different—darker and less enlightened. Distressingly, the United States is now filled with echoes of George Bailey's nightmare. It seems that some people are dismissive of the beneficial effects of evidence-based approaches on our lives. Available evidence, even when quite substantial, is ignored or minimized. Non–evidence-based approaches are treated as equally likely as evidence-based ones to lead to factually correct, robust results. The federal budget proposal recently released by President Trump's administration includes draconian cuts for almost all research agencies. If implemented, these cuts will severely damage the U.S. scientific enterprise for years to come. Based on history, this path is likely to lead to decreased long-term technological innovation as well as poorly conceived public policy. </jats:p>

<jats:p>A roundup of weekly science policy and related news.</jats:p>

<jats:p>Hunters will cull reindeer in an attempt to contain outbreak of chronic wasting disease.</jats:p>

<jats:p>“Western Stemmed points” may be the signature of ancient migrants who spread south along the Pacific coast.</jats:p>

<jats:p>Their ideas about science are sketchy, but Marine Le Pen and Emmanuel Macron have vastly different world views.</jats:p>

<jats:p>Pieced-together viral genomes contradict view that giant viruses represent a distinct branch of life.</jats:p>

<jats:p>Pending acquisition of Syngenta could speed approvals of biotech food crops.</jats:p>

<jats:p>Hunger amplifies infectious diseases for millions fleeing the violence of Boko Haram.</jats:p>