Gene editing has been an important biotechnological tool aimed at altering and correcting DNA. This technology could decrease risk for disease and change physical features. Due to these powerful scientific implications, there are also ethical issues involved, such as the occurrence of undesirable changes in the genome, how informed consent is obtained and the breeding of the human species.
A new method for gene editing is a technology called Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR). While this technology is in its infancy, it is particularly interesting to researchers because of its precision and low cost.
CRISPRs are specialized stretches of DNA that exist in bacteria as defense mechanisms against invading viruses. They help the bacterial cells detect and destroy invaders.
Researchers have been able to adapt CRISPR sequences to edit genomes. CRISPR is able to pinpoint sections of DNA and precisely cut it at a particular location, allowing the genome to be cut and modified.
Researchers begin by creating a short “guide” sequence of ribonucleic acid (RNA), which is a molecule that is essential to the regulation and expression of genes. First, the guide sequence binds to the Cas9 enzyme, which functions like a pair of “genetic scissors” and has the ability to “cut” DNA. Then, this guide acts like a “Google search” because it has the ability to search through large amounts of genetic material and line up with the specific section that researchers want to target.
After the guide sequence recognizes the specific DNA sequence the researchers want to target, the Cas9 enzyme cuts the DNA at that targeted location. This allows researchers to activate, deactivate and modify specific genes.
CRISPR can be used to treat disease by generating mutants or silencing genes. There are also several industrial uses for CRISPR as it can be used to create genetically modified crops and to develop vaccines.
Gene editing with CRISPR is used on two different cell types: somatic and germline. Germline cells are reproductive cells that eventually form embryos, sperm and oocytes. When targeting germline cells, effects can be felt for multiple generations due to their ability to pass on genetic information. Somatic cells refer to the rest of the body cells, excluding reproductive cells. Changes in somatic cells will not be passed down generationally. Using CRISPR to edit either type has ethical implications.
Off-target mutations in both germline and somatic cells can result in negative health implications. Off-target mutations refer to nonspecific and unintended genetic modifications that can arise through the use of CRISPR. These could lead to very harmful effects on organisms, potentially even resulting in cell death.
Germline editing also has a high risk factor because it can alter the genome of future generations. If there is some type of failure while editing the germline, undesirable mutations, side effects and other negative changes can also be inherited. This is especially risky because there is a lack of informed consent for offspring of future generations.
Informed consent is the process in which a health care provider educates a patient about the risks, benefits and alternatives of a given procedure or intervention. The patient, then, makes a voluntary decision about whether to undergo the procedure or intervention.
CRISPR violates informed consent. When it is used to edit the germline, the affected unborn fetus cannot give consent to take part in the experimental procedure or manage any complications or undesirable mutations that might arise as a result of the edited germline. Therefore CRISPR violates the fundamental tenet of medicine of providing informed consent.
Additionally, there must be a line drawn between using CRISPR for genetic correction and for genetic enhancement.
Genetic correction refers to the prevention and treatment of disease, while enhancement has been defined as boosting our capabilities beyond the species-typical level or statistically normal range of functioning, according to the National Science Foundation.
While genetic correction poses some ethical concerns regarding which diseases and disabilities should be targeted, genetic enhancement may result in dangerous social implications.
Using CRISPR germline editing for non-therapeutic reasons may allow for a new age of eugenics. Proponents of eugenics believed that the human population can be improved by controlled breeding to increase the occurrence of desirable heritable characteristics, according to a study at Yale Medical School.
Eugenics has been historically harmful because it promotes certain physical and personality traits and condemns the rest. It has led to the forced sterilization of thousands of Americans during the Eugenics Movement of the 1900s and mass genocide in Nazi Germany.
For example, if parents use CRISPR to select for a specific eye color or skin tone, they will likely choose the most socially preferred traits. As a result, increased discrimination and prejudice may follow for those who stray from those specific traits.
Using CRISPR for feature enhancing reasons has also been shown to be unpopular among Amercians. A poll from the Center of Genetics and Society indicates that 72% of Americans are opposed to using CRISPR to change an unborn fetus’s genes to alter physical features, such as eye color or height. This could be due to the potential negative impacts of eugenics.
If more research is done and CRISPR can become more widely adopted for both correcting and enhancing reasons, there are also socioeconomic implications to consider.
If CRISPR does become integrated in healthcare on a wider scale, it can be used in assisted reproductive technology, which is used to treat fertility through methods such as in vitro fertilization (IVF) — a series of procedures that allows for an egg to be combined with sperm outside of the body. Using CRISPR in this context would allow individuals to selectively edit features of their future children — characteristics which can range from simple cosmetic changes to life saving genetic alterations. However, IVF is also very expensive.
Another ethical issue that may arise is unequal accessibility due to the cost barrier. If only wealthy individuals had access to CRISPR, an unfair health advantage could be established, meaning that socioeconomic status may play an even larger role in the onset of diseases and the quality of treatment.
For example, wealthier groups may become genetically exempt from diseases like Alzheimer’s or cystic fibrosis through their access to CRISPR. However, these diseases will continue being a problem for economically disadvantaged groups.
While CRISPR has the potential to improve health and minimize risk of disease, more research and observation should be conducted before it becomes widely adopted. In the case that its efficiency and precision increase enough to become integrated with healthcare on a wide scale, this biotechnological tool should be used only for disease prevention and correction as opposed to feature enhancements.