Recent advances in genetics have afforded the ability to precisely manipulate every letter of our genetic code. Several world-renowned biologists, however, have called for a moratorium on using this technology to modify human DNA that can be inherited by future generations. Adapted from bacterial immune systems, the CRISPR-Cas9 system has been used extensively to modify the DNA of human cancer cells in test tubes, but it has not yet been used in the clinic. Proponents of the CRISPR-Cas9 ban cite our poor understanding of the potential repercussions of intentionally altering heritable genetic information.
This raises the question, however, of what will happen once we determine what those consequences are. Many physical human characteristics – such as height, beauty, and intelligence – are determined by hundreds of genes, so altering those factors via gene editing will likely be impractical. Furthermore, when society also considers the complex ethical questions that surround this “designer human” paradigm, the costs will likely vastly outweigh the benefits. A more reasonable application of CRISPR-Cas9 technology, however, would involve altering a single gene to prevent transmission of a debilitating genetically-inherited disease. Which diseases are “worthy” of this type of therapy, where the therapeutic benefits clearly override the many potential costs? How do we behave pragmatically without compromising our morals? The answers to these questions are far from obvious, but the discussion should begin now.
Acknowledgments: Many thanks to Dr. John Doench, Senior Group Leader in the Genetic Perturbation Platform at the Broad Institute, for providing his expertise and commentary on the topic.
Managing Correspondent: Christopher Gerry
Original article: A prudent path forward for genomic engineering and germline gene modification – Science
Media coverage: Scientists Seek Ban on Method of Editing the Human Genome – The New York Times
Related SITN article: CRISPR: A game-changing genetic engineering technique