We stand at the cusp of a new era of human reproduction where parents can choose to have babies with specific genetic traits. Companies like Californian start-up Orchid are starting to offer embryo screening which allows prospective parents to identify the healthiest embryo for pregnancy by identifying defective genes. A natural progression of the In Vitro Fertilization (IVF) technology that originated in the 70’s allows genetic screening and diagnosis of the embryo prior to implantation, enabling doctors to selectively implant embryos that are devoid of certain genetic defects.
While Preimplantation Genetic Diagnosis (PGD) gives parents
the ability to screen for severe, life-threatening (or life-limiting) inheritable
diseases like cystic fibrosis and Huntington’s disease on one hand, it also
opens up the possibility of something scientists have warned against for
decades – designer babies! A designer baby is a genetically engineered baby with
specially selected traits ranging from lowered risk of disease to enhanced physical
and mental characteristics.
Unlike the early offerings of embryo screening that focused
on life-limiting diseases like Down syndrome and muscular dystrophy, and
targeted couples with a high risk of having a child with such diseases, companies like Orchid are opening up genetic testing and embryo selection to the wider population and offering screening for more common illnesses such as heart disease and
diabetes as well. It is only a short jump from genetic selection based on health to genetic
selection of human traits like intelligence and appearance, and eventually, genetic
enhancement of such traits.
The groundbreaking CRISPR genetic engineering technology has
given scientists the ability to edit or modify genes. Advancement of CRISPR has
led to CRISPR-CAS9, which allows the modification of DNA fragments by adding/ removing
certain types of genes from a DNA molecule. It has brought us closer to a
gene-edited embryo.
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| Gene Editing Using CRISPR- CAS9 |
While the potential to prevent and cure diseases like breast
cancer (with removal of BRCA2 gene) is an exciting prospect, this latest
advancement of gene editing technology opens the floodgates to ethical and
moral debates on human control over reproduction. As the technology advances
and becomes common, it will blur the line between optimizing for health and for
physical and mental quality. Giving parents the ability to select embryos without
propensity to a disease can and will inevitably lead to demand in selecting attributes
like gender, eye color, appearance, intelligence, and athleticism. And in fact,
there is already evidence of PGD being used for gender selection wherein a Virginia
couple selectively opted for a female embryo to grow their family of two boys.
That day is not far when this seemingly far-fetched, science-fictionesque idea of designer babies becomes a reality. It is already known that a single gene produces the performance-enhancing hormone EPO; therefore, selecting embryos containing this gene could result in enhanced athleticism, for instance. Some fertility clinics in New York and elsewhere are already advertising on their websites the possibility of producing designer babies – not just devoid of unfavorable traits like genetic disease but also enhanced with favorable traits like enhanced intelligence and strength! It is also telling that almost 20% of respondents in a Pew Research Center poll conducted in 2018 supported the use of gene-editing to make a baby more intelligent!
Editing human genes, i.e., modifying human DNA in any way,
has been considered off-limits for ethical and moral reasons, and because of
the inherent risk of tampering with something that can be passed down for
generations. It is noteworthy, however, that unlike in Europe, the laws on human gene-editing research are sketchy in key countries, including the U.S., China and Russia. Not surprisingly, these countries are
the ones leading research in this area. It has been widely reported that
Chinese researchers are actively pursuing gene-editing of embryos targeting the
HIV-causing gene, CCR5; and a Chinese scientist made claims recently about creating
the world’s first genetically modified twins.
Also recently, an international team of scientists from the
U.S., China and South Korea, demonstrated the successful editing of the DNA in
a human embryo to fix a disease carrying gene. While lauding it as a “technical
tour de force,” the Dean of Harvard Medical School, George Daley, also highlighted
the dilemma presented by such research saying, "This is a strong statement
that we can do genome editing. The question that remains is: 'Should we?'”
Scientists are driven by a desire to understand science, often
steering clear of ethical and moral considerations. However, as a society, we have a
moral obligation to have a discourse on the ethical implications of gene
selecting and, more importantly, gene editing. Less than a century has passed
since the horrors of the Holocaust, which was driven by the Nazi quest for
racial fitness and dominance. Is the ability to select a baby with “desirable” traits
any different from the concept of eugenics that was also practiced during
Hitler’s regime?
Ethical arguments aside, the science and practical implications
of gene editing in humans is also fraught with dangers of unknown and
unimaginable consequences. As geneticists have argued, there is rarely a single
gene responsible for most illnesses, particularly for common diseases like
heart disease and diabetes. Therefore, screening for such diseases requires
using polygenic risk scores to assess the embryo’s risk of developing the
disease over a lifetime. Selecting genes that lower one
disease might in reality increase the risk of developing something else. For
example, eliminating the gene responsible for sickle cell anemia can reduce
protection against malaria. Without a much deeper understanding of genetics,
such gene-editing technologies could be a disaster in the making for future
generations.
Another point that is often overlooked in the ethical debate
about gene editing is the inherent inequity that it will produce. Not only will genetic alteration technology be primarily available to the population of developed
countries, but it will also be more effective for such populations, given
that the DNA databases compiled by researchers and private companies are highly
Eurocentric. Furthermore, there is a risk of growing stigmatization of
disabilities and illnesses if such conditions are increasingly edited out.
As Voltaire (and more recently, Spiderman’s uncle)
cautioned, “With great power comes great responsibility.” Playing God with
genetic engineering can have consequences beyond the scope of understanding and control of
mortals.
Sources:
https://www.newhopefertility.com/designer-babies/
https://www.pewresearch.org/science/2018/07/26/public-views-of-gene-editing-for-babies-depend-on-how-it-would-be-used/ps_2018-07-26_gene-editing_0-01/
https://www.technologyreview.com/2018/11/25/138962/exclusive-chinese-scientists-are-creating-crispr-babies/
https://asm.org/Articles/Cultures-Magazine/Volume-4,-Issue-4-2017/The-Designer-Baby-Distraction
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