-A British researcher has received permission to use a powerful new genome editing technique on human embryos, even though researchers throughout the world are observing a voluntary moratorium on making changes to DNA that could be passed down to subsequent generations.

The British experiment would not contravene the moratorium because there is no intention to implant the altered embryos in a womb. But it brings one step closer the fateful decision of whether to alter the human germ line for medical or other purposes.

The new genetic editing technique, known as Crispr or Crispr-Cas9, lets researchers perform cut-and-paste operations on DNA, the hereditary material, with unprecedented ease and precision. Unlike most types of gene therapy, a longstanding approach that aims to alter only adult human tissues that die with the patient, the Crispr technique could be used to change human eggs, sperm and early embryos, and such alterations would be inherited by the patient's children. Because changing the human germ line is perceived to hold far-reaching consequences, the leading scientific academies of the United States, Britain and China issued a joint statement in December asking researchers around the world to hold off on altering human inheritance.

A British regulatory agency that oversees reproductive biology, the Human Fertilization and Embryology Authority, on Monday approved an application by Kathy Niakan, of the Francis Crick Institute in London, to alter human embryos with the Crispr technique. Dr. Niakan, a developmental biologist, has no intention of implanting the altered embryos in a womb. According to a report in Nature, she will let the embryos expire when they are seven days old and have reached the blastocyst, or implantation, stage. The usual source of such embryos is fertility clinics that have generated more than their clients need...

http://www.nytimes.com/2016/02/02/he...n-britain.html