RNA genome editing
(Used in COVID-19 RNA Vaccines)
RNA editing (also RNA modification) is a molecular process through which some cells can make discrete changes to specific nucleotide sequences within an RNA molecule after it has been generated by RNA polymerase.
DNA genome editing
(Used in COVID-19 Viral Vector Vaccines)
Gene editing is performed using enzymes, particularly nucleases that have been engineered to target a specific DNA sequence, where they introduce cuts into the DNA strands, enabling the removal of existing DNA and the insertion of replacement DNA.
World Medical Association - Statement on human genome editing (Oct 2020)
Excerpt:
Genome editing, enabled by recent scientific advances, can generate targeted insertions and deletions in DNA and may even offer enough precision to modify a single base pair within the genome of an organism.
Basic science research with genome editing is now underway in laboratories globally. Human genome editing is also advancing rapidly, with clinical trials now in progress for prevention and treatment of various human diseases. These trials, which are currently in early stages, involve somatic (non-reproductive) cells, and thus are not anticipated to introduce genetic changes that will be passed on to offspring
or the germline (reproductive) cells.
While genome editing holds great potential to help improve human lives, the technology raises profound safety, ethical, legal, and social concerns. These concerns are compounded by the fact that regulatory and ethical guidance often lag rapid technological developments.
Safety concerns for genome editing
Unintended or unforeseen pleiotropic effects
Pleiotropic effects of a drug are actions other than those for which the agent was specifically developed. These effects may be related or unrelated to the primary mechanism of action of the drug, and they are usually unanticipated.
Off-target effects
These include unintended point mutations, deletions, insertions, inversions, and translocations.
Unwanted on-target modifications (imprecise edits)
Mosaicism (when only some cells carry the edit)
Abnormal immunological responses
The effects of epigenomic changes (changes relating to or arising from non-genetic influences on gene expression) are unpredictable, and there is disquiet as to how this will affect the existing healthy biological systems, including interactions with other genetic variants, and societal norms.
Once introduced into the human population, genetic alterations would be difficult to remove and would not remain within any single community or country. The effects could remain uncertain for many subsequent generations, during which time deleterious modifications could be dispersed throughout the population.
The WMA reaffirms principles in the Declaration of Reykjavik on the ethical considerations regarding the use of genetics in health care, the Declaration of Taipei on Ethical Considerations regarding Health Databases and Biobanks and the Declaration of Helsinki.
Declaration of Helsinki
Declaration of Reykjavik
Declaration of Taipei
Additional Sources
The history of RNA vaccine technology
COVID-19 Vaccine technology
Vaccines and genetic modification
COVID-19 Vaccine Delivery platforms
Pfizer BIOTECH Vaccine Approval
MODERNA Vaccine Approval (FDA)
JANSSEN Vaccine Approval
Oxford AstraZeneca Vaccine Approval
What are genome editing and CRISPR-Cas9?
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