CRISPR fills me with a bunch of dirty, conflicted feelings. Since last Thursday, I’ve watched the CBSN CRISPR story 3 more times, in addition to other interviews and stories to try and untangle the mess left inside me. Before I go any further, I feel compelled to state that I have the deepest respect for medical research, (researchers,) and the tremendous advances to extend and enhance our quality of life. I truly believe that the majority of people who become scientists and doctors do so because they possess a fundamental desire to be of service for ‘the greater good’ in some way.
Without further adieu, the number one reason CRISPR makes me so uncomfortable is because it is an alteration of an organisms (such as, a human’s) DNA and as most people know, mutations of DNA are the cause of cancer. For example, some may say that CRISPR would allow us to edit an inherited BRCA1 or BRCA2 mutation, which sounds promising because when someone inherits a mutated BRCA gene, the likelihood of that individual getting cancer is significantly increased. Such a scenario sounds like the perfect application for CRISPR. However, what happens if the CRISPR gene edit itself triggers cancer in the same patient, since it is essentially a mutation? Imagine taking a preventative measure that spirals into a total nightmare. (A-la Chernobyl, perhaps.)
As it turns out, my layperson’s imagined worst case scenario actually isn’t so far off. CRISPR-CAS9 typically works by cleaving both strands of a DNA’s double helix. Such an injury signals a cell response by a gene called p53, which either fixes the cuts in DNA or induces cell death. From what I understand, healthy cell function seems to be a source of concern or frustration for some CRISPR scientists because p53 is responsible for either repairing or terminating the DNA before the new gene is installed. So how is this linked to cancer? Of the cells that survived with CRISPR edits, scientists discovered the successful cells all had something in common: a malfunction in the p53 gene, which is often linked to cancer. For example, p53 failure causes approx. 50% of ovarian cancers, 43% of colorectal cancers, 38% of lung cancer and 25% of breast cancers. The takeaway here is that the cellular dysfunction that enables successful CRISPR DNA editing would also make them more likely to cause cancer. (Begley 2018, Wellenstein 2018).
One aspect that we saw in the CBSN CRISPR report that has kept me in a state of mental paralysis surrounding the subject of gene editing occured at the Lai pig farm. I found it extremely unsettling to see so many mutated pigs as test subjects; apparently there are hundreds of individuals. I don’t want to be naive, nor do I want to make it a 'cultural' thing because the cosmetic industry in the US alone has been responsible for practices that may be as cruel, all in the name of beauty. My biggest stumbling block regarding the pigs (aside from the high volume of individuals, as well as the inherent cruelty of it,) may be the understanding that: before the scientists give a pig cancer, or simultaneous diseases, such as Parkinson’s and Alzheimer's, they suppress the natural immune systems of the pigs. Lai said that they wanted to work with pigs because their immune systems are strikingly similar to humans, therefore it surprised me that the same basis for that justification is seemingly thrown out. To me, it felt lawless. As an aside, I would imagine keeping groups of immunosuppressed and diseased individuals in small, confined living conditions may be a confounding variable in Lai’s experiments. However, I’m not a real scientist yet, so I may be wrong; it’s just a thought. I’ve tried to step back and understand the scientific basis for these experiments, however, I haven’t been able to yet. (CBS 2017).
CRISPR is a vast, highly controversial topic; so much so that I feel like I’ve barely skimmed the surface of two small aspects of it. As I continue to try and process my deluge of thoughts, the one I keep coming back to, is that there isn’t a new piece of technology or technique that may allow humans to “play God,” as if we don't already. We have been acting as the masters of our own universe for quite some time. Humans don’t generally look at a mountain range and think, “how may I integrate myself into that existing ecosystem? How may I keep my disturbance to a minimum?” Far from it. Humans live as though everything and everyone (non-humans, mostly) that we see is ours. CRISPR won’t be a gateway to “playing God”; it’s just another one of God’s tools.
Begley, Sharon. “CRISPR-Edited Cells Linked to Cancer Risk in 2 Studies.” Scientific American, 12 June 2018, www.scientificamerican.com/article/crispr-edited-cells-linked-to-cancer-risk-in-2-studies/.
“Playing God: ‘We Are in the Midst of a Genetic Revolution.’” CBS News, CBS Interactive, 6 Nov. 2017, www.cbsnews.com/news/playing-god-crispr-dna-genetic-ethics/.
Wellenstein, Max D., and Karin E. De Visser. “Cancer-Cell-Intrinsic Mechanisms Shaping the Tumor Immune Landscape.” Immunity, vol. 48, no. 3, 2018, pp. 399–416., doi:10.1016/j.immuni.2018.03.004.