The Case Against CRISPR Gene Editing, Part II
By: Nita Jain
Tags: Ideas, Science, Education, Technology, Health

The Case Against CRISPR Gene Editing, Part II

On designer babies, gene reference libraries, and more

Speculation surrounding “designer babies” is based more in science fiction than scientific fact.

“Man is a maker and a selector and a designer, and the more rationally contrived and deliberate anything is, the more human it is.”

— Joseph Fletcher, one of the founders of bioethics, 1971

Photo by 0sart on Adobe Stock

Basic research on gene editing and the use of somatic gene editing to heal individuals who are sick are generally widely accepted among the public. The waters become murkier when we consider germline editing and the possibility of preventing disease or altering traits unrelated to health needs. In the 1970s, scientists first began to establish distinctions between somatic and germline genome modifications; somatic edits only affect a single individual while germline edits can be passed down over generations.

By the mid-1980s, bioethicists began to argue that the morally relevant line was between disease and enhancement rather than somatic and germline. Discussions of heritable enhancements in particular raise fears of a possible return to eugenics. “Designer babies” is a term commonly used in the vernacular to refer to babies with genetic enhancements. John Fletcher, former head of bioethics at the National Institutes of Health (NIH), once wrote,

“The most relevant moral distinction is between uses that may relieve real suffering and those that alter characteristics that have little or nothing to do with disease.”

Many scientists today share the sentiment that treatment and prevention of “disease” constitute acceptable uses of CRISPR technologies while “enhancement” applications should be discouraged, but the boundary between the two is riddled with semantic discord. Pharmaceutical companies frequently invent new medical diseases in a process known as medicalization. Neither can the medical profession be relied upon to make the distinction, as many plastic surgery practitioners conduct procedures that can more aptly be described as enhancement. Moreover, the line delineating disability and disease is often blurred, and many perceived shortcomings may in fact represent normal variation on the phenotypic spectrum.

The discussion of whether we can or should modify human characteristics may be a moot point since our knowledge of which genes affect complex traits such as height, intelligence, and eye color is still limited. Additionally, most traits are influenced not only by genetics but also environmental factors, and monozygotic twin studies demonstrate that genes alone cannot predict whether physical traits will be expressed. Furthermore, genes that encode for physical traits may also impart increased vulnerability to certain diseases. For example, variations in the MC1R gene responsible for red hair color may also increase the risk of developing skin cancer. The efforts of Dr. He Jiankui to confer HIV resistance to twins Lulu and Nana may have also resulted in increased susceptibility to infection by West Nile virus or influenza. As always, trade-offs exist, and the idea of the “perfect specimen” is a fallacy. Any efforts to gain genetic advantages will always be subject to the limitations of biology.