THE ALARMIST PHRASE "HAS SCIENCE GONE TOO FAR?" used to be reserved for those “Is This Image Real or Fake?” ads on Myspace showing a horse with a shark’s head. Nowadays however, we may have finally reached the point where we must seriously ask whether or not science has overstepped its ethical boundaries.
Recently, scientists themselves have been questioning the ethical implications of the CRISPR-Cas9 genome editing system. This system provides a way to easily create precise and controlled mutations in the DNA of organisms. Basically, scientists can use a protein called Cas9 along with short sequences of RNA to target specific genes. The technology has developed to the point where people are beginning to worry that it will be applied unethically to human cells, and with good reason too.
The biggest worry is that people will try to use the system to perform modifications in the human germline, which include human eggs, sperm, and embryos. Germline modifications are passed down from generation to generation, so if a mistake were to be made that generates some new disease, it would be passed on for many years to come.
In 2015, Chinese scientists published a paper in Protein & Cell describing their efforts to use the CRISPR-Cas9 system on human embryos. The scientific community was so wary of the paper that Nature declined to publish it. This is such a landmark paper because it reports the first attempt to edit human pre-implantation embryos. This paper demonstrated that the CRISPR-Cas9 system is not ready for use in humans yet due to a large number of off target effects, raising questions about how safe the technology is for humans and animals.
Scientists have been so excited by CRISPR-Cas9 because it can potentially be used to cure many genetic disorders such as sickle cell anemia, cystic fibrosis, and cancer. However, this opens a Pandora’s box of other issues. One big issue is that the ease of genome modifications may lead to “designer babies,” in which parents can hand pick the physical features that they want their child to have.
Due to ethical concerns about the use of the CRISPR-Cas9 system on human germ lines, scientists organized a summit in Napa, California in 2015 to discuss these issues. Scientists, including Jennifer Doudna, who helped develop CRISPR, and two Nobel laureates, are strongly encouraging a moratorium on the application of CRISPR-Cas9 technology on human germ lines, at least until we better understand how safe the system is. Some scientists argue that this only inhibits the advancement of science, but it seems like science will need to be careful of where it takes its steps for the time being.
This call for a moratorium does not mark the beginning of the end for CRISPR-Cas9 however. Similar questions regarding genetic modifications were prevalent when recombinant DNA technology was first introduced several decades ago. However, recombinant DNA technology has been one of the most influential technologies of the last century, and hopefully the CRISPR-Cas9 system can even further advance our understandings of genetics without leading to the creation of Build a Baby workshops across the world.
Y. Daniel Lee is a junior from Lovett College at Rice University.
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