Science has chosen the genome editing method called CRISPR as its 2015 Breakthrough of the Year, an "unprecedented selection," Managing News Editor John Travis explains, given that the technique appeared twice before among Science's runner-ups, and is the only runner-up to subsequently be elevated to Breakthrough status. Science placed CRISPR at the top of their annual list of scientific breakthroughs given fresh demonstrations of its muscle this year, including the creation of a long-sought "gene drive" designed to eradicate a variety of pests, the first deliberate editing of the DNA of human embryos (controversial work performed by Chinese researchers last spring), and the CRISPR-driven deletion of 62 copies of a retrovirus' DNA in the pig genome, a move that paves the way for pig organs to be considered for humans awaiting organ donation. Travis's article highlights the superior ability of CRISPR to deliver a gene to the right spot compared to its genome editing competitors - as well as the technique's low cost and ease of use, qualities that have allowed thousands of labs, high school students, and "biohackers" alike to begin exploiting the 3-year old technique. "It's only slightly hyperbolic to say that if scientists can dream of a genetic manipulation, CRISPR can now make it happen," Travis said. The promise of this tool exists alongside continued debate about how best to regulate its use in plants, animals, and people, with the topic of human genome editing discussed by an international summit in Washington, D.C., earlier this month. In a related Editorial, Marcia McNutt, editor-in-chief of the Science family of journals expresses hope that "in two years' time CRISPR will have brought to many diverse fields in biology the enduring level of excitement and optimism that immunotherapy [Science's 2013 Breakthrough] has brought to cancer patients."
This year's special Breakthrough section also includes the results of a readers' choice poll in which the public voted on its favorite science breakthrough, declaring the voyage of the New Horizons spacecraft past Pluto their winner.