Ever since the birth of the first "test-tube baby", Louise Brown, in 1978, IVF has been a heavily debated subject. Religion, politics, ethics, and social stigma have constantly shaped and swayed opinions on one of the main modes of treating infertility. One particular topic that seems to constantly come up is the topic of "designer babies".

Gene editing is no longer science fiction, it's reality.

In 2018, a Scientist, He Jiankui, used gene editing technologies to create a pair of HIV-resistant twin girls.  The problem? Gene-editing of human embryos is illegal, and Jiankui was sentenced to three years in prison for malpractice. To this day, the status of the twins with the HIV-resistant (CCR5) gene is not yet clear.

Genome editing in embryos requires the genes to be modified/altered at the embryonic level by using a molecule called CRISPR-Cas9. It was first discovered in bacteria as their mechanism to defend and fight against viruses. Cas9 protein identifies the virus target DNA with the help of a guide molecule and cuts the virus DNA, disabling the infection. The same technique is used by scientists in the laboratory to modify/alter the target gene by designing the guide molecule to introduce the cut at the target position and replace it with a known customised gene giving us the desired trait.  

In a world obsessed with perfection, the concept of being able to edit and create flawlessly designed babies seems an eventual inevitability. Unfortunately though, and putting the ethical argument of allowing such practices aside, the technology is not as accurate and clean as the “copy” and “paste” functions on a computer. The technology is prone to “off-target” hits, meaning the cutting out or adding-on of genes you would not want to be edited out (which can have potentially life-threatening effects). Especially as any unsuccessful alteration at the embryonic level can go through generations affecting the future born babies with the heredity of the unwanted traits. Another lesser understood and baffling phenomenon is one attributed to the treated cells expressing similar genes to the removed or modified ones in an attempt to compensate for the lost or altered genes, potentially nullifying the effects of treatment with CRISPR-Cas9.

Researchers and bioethicists believe that with the current evidence and data, gene-editing for reproductive purposes should not be done, as such CRISPR technology is only permissible in biomedical research (most recently, cancer research). Most countries have set strict regulations about the use of gene-editing technologies for reproductive purposes.

The only approved procedure done on the embryos is Preimplantation Genetic  Testing (PGT), where a small number of cells are biopsied and tested for the presence of genetic and chromosomal abnormalities before implantation.

It is yet to be seen how gene-editing technologies like CRISPR-cas9 can be introduced safely and ethically into fertility treatment. I see it one day being used to salvage human embryos that otherwise would have been discarded or deemed not suitable for use due to the presence of genetic abnormalities.

What are your thoughts? Can genetic editing be used ethically and safely in fertility treatment, or is there an ethical risk of the technology being abused?

Sameera Hayat

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