The Dark Side of Gene Editing?

Gene editing technology has erupted since the advent of CRISPR-cas9. And as with any technology, while there is great potential for good, people are also concerned about the lasting impacts gene editing could have on humanity.

One of the areas of great concern is germline editing. This area has a lot of ethical considerations society must discuss. But first, what is germline editing?

Germline Editing

There are two types of cells- somatic cells and germ cells. Most of the cells in your body are somatic cells- like your skin cells, or blood cells. And these cells don’t pass on their genetic information to any of your children.

So far, the majority of genome editing in humans has been done in somatic cells. And somatic cell modification is much less controversial.

However, it’s a different story for germ cells, like eggs, sperm, and embryos. These cells pass on genetic information from parent to child.

And that’s where the ethical concerns come into play. Any changes made to germ cells have the potential to be passed down to all future generations.

Current Consensus

Right now, germline editing isn’t socially acceptable in the scientific community. There are a few reasons for this hesitancy to embrace editing the germline. First and foremost, the safety of germline editing isn’t yet certain.

A commission, sponsored by the Royal Society in the U.K., the U.S. National Academy of Medicine, and the U.S. National Academy of Sciences, announced in 2020 that editing and using human embryos for pregnancies was not yet advisable. The potential for off target edits was too great.

“There are gaps in our knowledge and further research is necessary.”

-Katy Davis, co-chair of the commission and a genetics professor at Oxford.

But even if it becomes safe, the commission also said that the ethics still need to be discussed, due to the inheritability of any edits.

And since so many people could be impacted by genetically modifying the germline, it is important that as many people as possible are involved in the debate surrounding the ethics. And until then, it is best to hold off on genetically modifying future generations.

Editing future generations is so contested ethically partly because there’s no consent from the individuals having their genomes modified.

In current gene editing trials, participants are older, and can give their consent. Editing before birth removes that option.

So then the question is, will genetically modified children be ok with their genomes being modified?

That, unfortunately, we can’t really answer. So then it comes down to whether we’re willing to take this risk.

But within germline editing, there are two main types, each with their own set of ethical considerations- one of which is much more controversial than the other.

Therapeutic Edits

The most favored germline modification (as much as it is favored right now) is for preventing genetic disease.

For example, currently there are trials underway using CRISPR to treat patients with sickle cell disease. But what if we could treat those patients before they’re even born?

This is why these edits are less controversial- they’re preventing disease and hopefully improving children’s lives.

But, in addition to the uncertainty surrounding consent, this type of modification still involves its own set of ethics.

Some diseases, like Huntington’s disease, are fatal. These would be amazing to cure. But what about ‘diseases’ that don’t cause death or even harm one’s health? At this point, the line for what counts as a disease becomes blurry. And what counts as a disease varies from person to person.

There is a lot of negative potential consequences for therapeutic germline modifications. But despite that, there is a positive side. These edits could spare many people from suffering and create a world without genetic disease.

But therapeutic edits aren’t the only edits with complicated ethics. The other type are enhancements- and this is where designer babies come into play.


While therapeutic germline modifications are for preventing genetic disease, enhancements are just what they sound like- giving children better qualities, whether it’s height, athletic ability, or intelligence.

These edits are much more futuristic and much more controversial. ‘Designer babies’ is the term popularly used for the resulting children.

And there are a lot of things to fear about designer babies. These edits could widen socioeconomic gaps, as the rich are able to enable their children to be genetically better prepared for success.

Such an unequal society isn’t a new idea. The movie Gattaca, released in 1997, more than a decade before CRISPR, takes place in such a world, where those who aren’t genetically modified aren’t able to hold certain jobs and are treated as second class citizens.

Again, as with therapeutic edits, there are reasons for such enhancements. If we could improve the human race this way, imagine the future we could create.

It’s also uncertain how much we could control for traits like intelligence or height. These traits have many genes affecting them, and are also influenced by one’s environment.

And while there are a great many decisions society must make regarding the ethics of germline editing, some scientists have proposed or even performed edits in embryos.

Genetically Modified Children

In 2018, a researcher announced the birth of twin girls who had been genetically modified to be resistant to HIV, and that was met with uproar. Later, in 2019, another scientist announced intentions to edit embryos to also be resistant to HIV, although he later refocused on a gene that causes deafness. However, he said he wouldn’t implant any edited embryos without the approval of the health ministry.

These examples show how urgent agreements on the ethics of germline editing are. Gene editing technology is moving quickly, and it is vital that we don’t fall behind. This is a debate for all of society too, because everyone will be affected by the outcome.


  • Editing the germline creates edits that can be passed down to future generations.
  • This raises the ethical concern about changing children’s genomes.
  • Therapeutic edits aim to prevent genetic diseases, but it’s not always clear what counts as a ‘disease’.
  • Germline enhancements could create designer babies, and create an unequal society; on the other hand, it could also increase the human race’s potential.

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