Eugenics or Curing Cancer? The Bioethical Concerns Surrounding Genome Editing

“Genetic scissors” or CRISPR-Cas9 is a laboratory tool used to edit genomes by removing, adding, or altering sections of DNA sequence. CRISPR stands for Clustered Regularly Interspaced Palindromic Repeats, which describes the region of DNA made up of short, repeated sequences with "spacers" sandwiched between each repeat, and Cas9 is the enzyme capable of cutting through DNA. CRISPR allows for correcting errors in the genome and turning genes in cells and organisms on/off quickly and easily. It has been used for curing mice of genetic disorders by repairing defective DNA, gene therapy, treating diseases such as HIV, and engineering autologous patient material to treat cancer and other diseases. CRISPR sequences are transcribed into RNA sequences (crRNAs), which guide the system to match DNA sequences. When the target DNA is reached, Cas9 binds to the DNA, cuts it, and shuts the targeted gene off. These three steps are known as recognition, cleavage, and repair. 

The E. coli CRISPR was originally found in 1987, and the first use of the CRISPR-Cas9 complex was in 2007 when it was discovered that the CRISPR region cooperated with the Cas proteins produced from the genes located next to the CRISPR. The official “inventors” of the CRISPR-Cas9 system are Emmanuelle Charpentier and Jennifer Doudna, who won a Nobel Prize in Chemistry in 2020 for their key discoveries in DNA manipulation. When it was first founded, the CRISPR–Cas9 system's original biological function was protecting prokaryotes from mobile genetic elements in certain viruses. Still, since its introduction to biotechnology, it has been used for much more thanks to these two women. 

The benefits of CRISPR-Cas9 include its lower off-target effects. Using CRISPR nickase to alter one nuclease domain in only one strand of DNA is an effective method for reducing off-target effects. Furthermore, Cas9 D10A nickase produces single-strand breaks and cleaves targeted strands. It can also be used to insert new DNA as with CRISPR, it's easy to insert a new sequence at the precise spot needed. This method has greatly changed biomedical research as it minimizes the expense of having to develop animal models with specific genomic changes. Finally, it has higher gene editing efficiency. Since the CRISPR-Cas9 system is capable of cutting DNA strands itself, CRISPRs do not need to be paired with separate cleaving enzymes as other tools do. Recently, the editing efficiency of CRISPR has risen to 66.7%

Some disadvantages include the potential for off-target genome editing effects, as it can induce site-specific DNA mutations in human DNA. New research shows that these mutations can be inherited by future generations. A main ethical concern is stigmatization, as genome editing to treat diseases or disabilities could lead to stigmatization of people with those conditions, and the idea that genetic differences count as diseases or defects already plagues our society. Another concern is Eugenics, or practices to improve the genetic quality of the human population. Germline and embryo editing could create hierarchies and classes of people characterized by their “desirable” traits, and CRISPR has already proven the harmful ability to alter skin color (a study in which the fur color of rats was successfully changed).

Overall, this piece of biotechnology is morally concerning because if used by the wrong people or for the wrong thing it could be detrimental to our society, however, if it develops to be; accessible despite income, limited and not prescribed casually, and professional (used for the correct issues and not to edit for individual or societal enhancement), it will be an amazing technology that could further human quality of life and society as a whole.