1) What is CRISPR and how does it work?
CRISPR is a set of DNA sequences included in the genomes of bacteria. Natively, bacteria use CRISPR to protect themselves from viruses. Through extensive research, scientists have repurposed CRISPR to target and modify specific genes. CRISPR technology uses “guide RNA” (RNA is a close relative of DNA) and a protein called Cas9. Guide RNA binds at the site to be modified within a gene and “guides” Cas9 to that site, allowing Cas9 to cut the gene. Afterward, the gene undergoes a natural process called “homologous recombination” that modifies the DNA and seals the cut.
2) What can CRISPR be used for?
At the most basic level, CRISPR is a gene-editing tool, which means that it can be used to alter or customize the genome of an organism. The applications of CRISPR technology are extensive because DNA is the foundation of life. Thus, genetic diseases that are otherwise unsolvable could be treated and even cured by using CRISPR to modify the harmful copy of the gene. Research has also begun on using CRISPR in human embryos to prevent terminal genetic disease before the baby is even born. In terms of gene editing, there are a myriad of different applications. However, perhaps the most likely application to surface in the near future is in the field of biomedicine for treatment of genetic disease.
3) How can we use CRISPR technology in medical practice without risking the possibility of someone taking it too far? How do we draw the line between what is beneficial and what is not?
We do not know how to draw the line yet. However, because it is important to understand everyone’s opinions about CRISPR gene editing first, there are certain steps we could take towards drawing the line. In addition to the efforts of the Committee on Human Gene Editing to develop ethical parameters (see question 5), we must hold conversations and discussions in the scientific community and as a broader community. Scientists who have access to CRISPR technology, medical professionals, and the general public should all be part of these conversations. We need to start addressing questions about the specific uses of CRISPR technology. For example, when should CRISPR be used as treatment? Should CRISPR be used as a preventative measure? Should each medical case be evaluated individually? No matter what we decide, the social and ethical consequences and risks should first be assessed.
4) What are the ethical implications of CRISPR? What are the potential risks and dangers of such a powerful tool?
CRISPR has many ethical implications. One of the biggest concerns is the application of CRISPR in human embryos. Using CRISPR in human embryos would create CRISPR babies, or “designer babies.” While CRISPR could be used to protect babies from a variety of hereditary genetic diseases, it could also be used to design a baby with certain traits. We could essentially create a new species. How would we manage this technology? Would our societal definition of “normal” as we know it be redefined? CRISPR also has some biological risks and dangers. If CRISPR is used to manipulate genes in germline cells, these manipulations will get passed down from generation to generation. Unintended changes in the genome might occur, and these changes, which could potentially be harmful, would be passed down to the next generation. Even the smallest mistake in this technology could have dire consequences. For example, a single mistake could create a new genetic disease. However, on some level this dangerous outcome isn’t special to CRISPR; we should keep in mind that errors are already being made in our genome on a daily basis, usually without much consequence.
5) Who is keeping track of and weighing the social and political implications of CRISPR, gene editing and GMO farming?
In 2015, researchers who were involved in developing CRISPR gene editing and policymakers representing science and medical academies around the world organized an “International Summit on Human Genome Editing.” The purpose of the summit was to start to address the social and political implications of gene editing. The summit resulted in a “Committee on Human Gene Editing: Scientific, Medical, and Ethical Considerations,” which was assembled by the National Academy of Science, the National Academy of Medicine, the Royal Academy of Sciences and the Chinese Academy of Sciences. The committee has published a report proposing criteria and guidelines we must consider for heritable germline editing and human genome editing. The efforts of this committee are critical because there is still ongoing debate over the regulations on CRISPR gene editing between governments and the scientific community.
The committee has also called for public education and engagement. This call-to-action inspired our Biochemistry class to engage the public. We are writing this package of articles to inform our community, so that all of you can participate in these conversations about gene editing and the implications of CRISPR gene editing. We believe that public engagement in these conversations is critical.
In the United States, regulations around GMOs are more established and concrete. GMOs are regulated and examined by the Environmental Protection Agency, the Food and Drug Administration, and the U.S. Department of Agriculture.
6) Are GMOs crops harmful to our health? To our environment?
Genetically-modified organisms, or GMOs, are any organism whose DNA has been intentionally altered. GMO crops have to be approved before being commercialized for human consumption. These crops are not thought to be harmful to our health, but they can have an impact on the environment. GMO crops have the potential to cross-breed with naturally occurring crops and out-compete these natural plants. Thus, by natural selection, the GMO crops could in theory dominate all plant crops.
This package was produced by Middlebury College students Emma White, Ashley Wang, Jeanelle Tsai, Hayden Smith, Emma Norton, Chloe Levins, Will Kelley, Anna Goldstein, Luna Gizzi, Cleo Davidowitz, Anthony Bongiorno and Liam Bent, under the direction of Lindsay Repka, Assistant Professor of Chemistry and Biochemistry.