Just weeks ago on September 28th, Japan’s governmental health and science ministries officially drafted national guidelines on human gene-editing and manipulation experiments, particularly within embryos (Cyranoski, 2018). Before then, Japan’s stance on genetic experiments had remained neutral. Now it is joining an increasing list of countries who support this genetic innovation.
One of the most intriguing and promising forms of gene-editing is a form of complex known as CRISPR-Cas 9. CRISPR or Clustered Regularly-Interspaced Short Palindromic Repeats, is composed of short 20-40 letter palindromic ATGC DNA sequences, spacer DNA, a single guide RNA (sgRNA) and a protein known as Cas9 (Zhang, 2016). The sgRNA acts as a guide for the Cas9 protein. It contains the information which directs the protein to the problematic genes. The role of the Cas9 protein is to detach the isolated gene using its 2 nuclease domains. Afterwards, the cell will attempt to repair the damaged sequence. Luckily, the repair process is particularly error-prone, and the Cas9 protein will typically succeed (Zhang, 2016).
While it is obvious this is an incredible advancement in the field of genome editing, it is obvious that there are some ethical concerns. Scientists are unsure of the risks and complications of genome editing within embryos and are cautious of whether CRISPR should be utilized for embryonic genome editing, especially in the near future (Doudna, 2018).
Jennifer Doudna, one of the main biochemists responsible for the creation of the CRISPR-Cas 9 complex is hesitant towards any embryonic genome editing. She has stated: “I think most people would feel that genome editing in adults [to eradicate genes responsible for diseases such as sickle-cell anemia] is a very appropriate technology. It might be analogous to taking a pill for treating cancer” (Doudna, 2015). “What certainly raises ethical implications is whether that sort of change should be made in an egg, sperm or embryo where those changes would then be passed on to further generations” (Doudna, 2015).
Genome editing within embryos is referred to as germline engineering (Callaway, 2016). One of the main ethical concerns of germline engineering is the embryo’s inability to give consent. What if the person whom that embryo will become did not want to have their natural genes changed? Director of the United States’ National Institute of Health, Francis S Collins M.D. is worried about what will become of scientists “playing God”. “Evolution has been working toward optimizing the human genome for 3.85 billion years. Do we really think some small group of genome tinkerers could do better without all sorts of unintended consequences?” (Collins, 2015).
The most prominent issue in genome editing in children and adults is off-target mutations. This occurs when the Cas-9 protein accidentally cuts the wrong gene causing it to potentially become at risk for causing an array of diseases. The likeliness of off-target mutations is extremely low within a single gene. However, if the CRISPR-Cas9 complex was being used on a larger scale on millions of cells the risk becomes far larger (Doudna, 2018). By using the CRISPR-Cas9 complex on a minuscule amount of cells the risk of off-target mutation is exponentially lower. Because of this risk, George Church is an advocate for germline engineering (Church, 2015). However, since 2015 Church has joined a group of 17 prominent figures within the field of CRISPR who are calling for a moratorium on the use of CRISPR in conjunction with embryonic cells. The moratorium is designed to give researchers time to evaluate all potential risks and complications and give a conclusive statement on the benefits and limitations of the CRISPR-Cas9 complex (Church, 2015).
The final major risk of pursuing the use of the CRISPR-Cas9 complex on embryos is the danger of creating genetic classism between those who can afford it and those who cannot. Journalist and CRISPR specialist, Nick Stockton believes “gene editing for therapeutic purposes [disease eradication] will inevitably lead to the creation of genetic classism” (Stockton, 2015). We as humans certainly do not want to create a society where some people are “purebred”, and the rest of the population continues to suffer from imperfections. Some scientists even believe this could lead to a re-emergence of segregation and possibly even genocide (Stockton, 2015).
Conclusively, it is obvious that CRISPR is a fantastic discovery for mankind. However, mankind must be careful to err on the side of caution as the risks of CRISPR are undeniable. We do not want to risk a divided society, or new hereditary diseases and conditions which could affect future generations for many years to come. Because of this, a moratorium on CRISPR-Cas 9 complex related experiments on human embryos must be enforced and regulated until we are absolutely confident in the results of our actions.
