Which explains the visceral effect of a postcard that came bundled with last week’s issue of Science magazine, advertising a genome editing kit that “delivers pre-designed plasmids and all the vectors needed to knock out any human or mouse gene.” The kit leverages a powerful new gene editing tool known as CRISPR/Cas-9, which many scientists believe has the potential to revolutionize medicine, agriculture, manufacturing, and more.
[CRISPR is an acronym for DNA sequences that are used by all plants and animals to defend against threats such as viruses. Biologists have recently figured out how to manipulate these sequences via enzymes called Cas-9, enabling new capabilities in editing the genomes of all living things. For a quick overview, check out Nature’sCRISPR: gene editing is just the beginning. Also, note that we’re not talking about editing the human germline (sperm or egg cells carrying genetic material to one’s offspring), something that may be technically possible in the future but for ethical reasons is opposed by most scientists.]
I’m not a professional scientist, so take my opinions with a grain of sodium chloride. But I think biology is special, and that we should be discussing these technologies and their implications, so we can make informed decisions about the future of our bodies and our societies. As both Voltaire and Spiderman know, with great power comes great responsibility.
To get a sense of the complexity of the issue, consider the case of golden rice, a rice strain that was developed more than a decade ago to combat vitamin A deficiency. Today, this deficiency still causes causes one to two million deaths annually, plus more than 500,000 cases of irreversible blindness. Why do people continue to suffer and die when a solution has been available for years? Because golden rice is a genetically modified organism (GMO), and thus has met significant opposition from environmental and anti-globalization activists.
I understand that many people who care about the environment want to prevent giants like Monsanto from using patented GMO plants to dominate agriculture, but GMO foods are not inherently dangerous, indeed humans have been genetically modifying crops via selective breeding for thousands of years.
What’s interesting is that CRISPR technology makes it possible to enhance a plant or animal by manipulating its own genes, rather than by transplanting genes from a different species. With CRISPR, one could modify an existing rice gene so that it makes a vitamin A precursor – without the addition of genes from any other species. The emerging consensus is that the result of such editing is not a GMO, and therefore would not be subject to the same social and political constraints. For example, earlier this year the US Department of Agriculture ruled that a white-button mushroom engineered via CRISPR so that it doesn’t turn brown so quickly “does not contain any introduced genetic material” and thus isn’t even subject to the agency’s GMO regulations.
- Chinese scientists have started human trials of CRISPR-engineered T-cells with patients who have metastatic non-small cell lung cancer and for whom chemotherapy, radiation therapy and other treatments have failed.
- A Swedish scientist has prepared and served an entire meal of foods genetically altered using CRISPR editing.
- Plant engineers at DuPont have created a drought-resistant strain of maize (corn) by using CRISPR to change how a single gene is expressed, without actually altering the plant’s DNA.
As sci-fi author William Gibson put it, “The future is already here — it’s just not very evenly distributed.”