Skip to main content

Playing God

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.  

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:

Comments

Post a Comment

Popular posts from this blog

Origin of Neurology

As I consider majoring in neurobiology (the study of the biological mechanisms that control the nervous system) in college, I thought it would be interesting to delve into the origins of neuroscience. For hundreds of years from the ancient Egyptians to the Greeks, humans believed that the seat of intellect was the heart (which is why the ancient Egyptians went to great lengths to preserve the heart after death but discarded the brain!)    The birth of neurology began 2500 years ago with Hippocrates who pondered over the purpose and functioning of the brain, reasoning that the brain must be the organ controlling sensation simply because most sensory organs - eyes, ears, and tongue -- are located close to the brain. This was starkly different from other opinions of the time which held that the heart was the main organ that controlled everything in humans. The brain was simply thought to be a "radiator" for pumping the heart and keeping it cool.  Later, Hippocrates expanded ...
Post a Comment
Read more

Galen

Even though Cajal is considered the father of neuroscience, his contribution came centuries after the first insights into the nervous system. As I wrote in my earlier posts, ancient doctors pondered over the nervous system, trying to understand what controlled the mind and body. Of these doctors, one that stands out is Galen, whose contribution to the understanding of the nervous system was fundamental to neuroscience. Through anatomical experiments, Galen was the first to observe and teach the functioning of nerves in the body. For these experiments, which he wasn’t shy about demonstrating to the public, Galen is regarded as the founder of experimental physiology. Galen is considered one of the most prominent and influential doctors in history, second only to Hippocrates. Galen was a staunch follower of Hippocrates and helped spread his teachings from Greece to the vast Roman Empire. Claudius Galenus, commonly know as Galen, was born in 129 AD in Pergamum in modern-day Turkey to a...
Post a Comment
Read more

The Nervous System

Just as the purpose of the brain and the heart confused ancient scientists, so did the nervous system. Nerves had been identified fairly early but they proved difficult to categorize. Some thought it was similar to arteries and formed some sort of connective system for tissues. In fact, the word nerve is Greek for tendon or sinew, suggesting that it was thought to be some sort of physical connection. Despite the confusion about its exact mechanism, ancient medical practitioners seemed to understand its function. Nerves were attributed to both movement and sensation correctly, even though there were opposing views on what controlled these functions. Aristotle argued that nerves originated and were controlled by the heart, while others argued nerves were controlled by the brain. Centuries later, Galen proved that nerves emanated from the brain, scoffing at those “who know nothing of what is to be seen in dissection." Galen was the first to conclude that the spinal cord was an ...
Post a Comment
Read more