By: Taylor Eisenstein
Genome editing procedures include meganucleases, zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the CRISPR/Cas9 system. The phrase “CRISPR” is short for “clustered regularly interspaced short palindromic units”. The CRISP/Cas9 system is often cited as the most recent, efficient, and cheapest of all these methods.
Genome editing can be used in a variety of ways. Somatic genome-editing therapies target the somatic cells, or the non-reproductive cells of the body. Since somatic cells are the non-reproductive cells, changes performed while editing are largely non-heritable and affect only the individual in question. Such therapies are usually intended to target and treat disease and disability within an individual.
For instance, last November, Chinese researchers used the CRISPR/Cas9 technique to modify cells in a lung cancer patient. They used the tool to disable a gene that codes for a protein called PD-1. The PD-1 protein plays a role in halting the immune response, therefore allowing cancerous cells to proliferate and invade the body. By editing the cells, the researchers hoped that they could facilitate a greater immune response to fight off the patient’s cancer.
In particular, for somatic cell editing procedures, the NAS report concluded that “the ethical norms and regulatory regimes developed for human clinical research, gene transfer research, and existing somatic cell therapy are appropriate for the management of new somatic-genome-editing applications aimed at treating or preventing disease an disability.”
Germline editing is usually far more controversial than somatic genome editing. Germline, or reproductive cells, are heritable; therefore, edits in the genome can be passed down to offspring. This procedure would benefit individuals with heritable diseases, since they could prevent their children from inheriting harmful mutations. It is significant to note that the Food and Drugs Administration (FDA) is currently prohibited from funding germline research.
The NAS report ultimately concluded that further research must be conducted and additional guidelines should be established before germline editing is used for humans. It stated, “Germline genome editing research trials might be permitted, but only following much more research aimed at meeting existing risk/benefit standards for authorizing clinical trials and even then, only for compelling reasons and strict oversight.”
While the report also mentions genome editing for enhancement purposes—such as to increase an average person’s muscle strength—it emphasizes that “genome editing for purposes other than treatment or prevention of disease and disability should not proceed at this time.”
Genome editing involves researchers, policy-makers, doctors, and other science-focused individuals—but it requires the input of the general public as well. The report even states, “Public engagement is always an important part of regulation and oversight for new technologies.” Many individuals have concerns regarding genome editing, especially in regards to religious beliefs. It is important for all individuals to communicate their concerns and discuss potential regulations before such procedures—in particular, germline editing—proceed in humans. Public discourse, along with expert opinion, is important in establishing a future for genome editing.