Almost twenty-five years ago, the scientific breakthrough of mammalian cloning marked a monumental moment for medicine and science. Anticipating the collision this would have with ethical decision-making in medicine, I, the only US Senate medical researcher at the time, traveled to the University of Edinburgh in Scotland to personally visit Sir Ian Wilmut in his research lab at the Roslin Institute. .
Professor Wilmut a few months earlier, in 1996, had cloned a sheep from an adult somatic cell, shocking the world. It was the first successful attempt of its kind. All over the world, people wondered: would we clone a human being next? We talked about science, we talked about ethics, and we talked about the potential impact of its creation on altering the course of human history. I also met and examined the cloned sheep, Dolly, in her stall.
Dolly, named after Dolly Parton of Tennessee, was a Finnish Dorset sheep cloned from a single adult mammary gland cell. Its creation, birth, and short life were scientific feats that immediately sparked global concern and discourse about the increasingly complex moral and ethical dilemmas posed by a sudden discovery of the manipulative science of life.
Wilmut and his colleagues published their feat in February 1997, after keeping Dolly a secret for seven months. As a society, we were quickly forced to answer difficult and probing questions. A few months later, in the Senate, I borrowed a question that the Washington Post editorial board had posed a few years earlier: “Is there a line not to be crossed even for scientific or other gain, and if so, where is it?
Here are my remarks to the Senate in 1998:
“It is therefore essential that our public debate and our reflection on scientific developments keep pace with, and even anticipate and prepare for, new scientific knowledge. The moral and ethical dilemmas inherent in human cloning may well be our greatest test yet. We seek not just knowledge, but the wisdom to apply that knowledge. As with every breathtaking scientific advancement of the last century, we know there is potential for good and bad in this technology. Congressional Record – February 2, 1998
Years later, I now think back to the confusion, the questions, and the status quo that Dolly challenged.
Why was Dolly so important?
Dolly was the first mammal to be successfully cloned from an adult somatic cell, that is, any type of body cell that is not a reproductive germ cell. The process developed by Wilmut is technically called “somatic cell nuclear transfer,” colloquially known as cloning. It is the process of transferring nuclear DNA from a donor somatic cell into an enucleated oocyte, followed by the development of the embryo, then transfer to a surrogate recipient, followed by a live birth.
The creation of Dolly in a test tube and her eventual birth marked a major milestone in scientific research, suggesting that an animal could be cloned to create an exact replica using genetic material derived from theoretically any type of body cell. He opened the world to amazing new possibilities in reproductive cloning and therapeutic cloning.
Shortly after Dolly was born, another parallel and equally monumental discovery was made: in 1998, embryonic stem cells were discovered. These cells are a very unique type of “unprogrammed” somatic cell with the exceptional ability to both reproduce unlimited exact copies of themselves and to develop into more specialized cell types, such as heart, lung, , renal or cutaneous. And although seemingly miraculous in potential, these cells could not be created or programmed from any other cell type and could only be collected from embryos – an ethical dilemma because collecting for research required the destruction of the embryo itself.
Dolly changed that. Its successful creation paved the way for future scientists to develop a technique to independently produce equally potent “pluripotent” stem cells by reprogramming other adult somatic cells, revolutionizing gene therapy and completely negating the ethical dilemma of collection of embryonic stem cells from embryos. Similarly, Dolly also highlighted the potential for scientists to create new tissues and organs for sick patients and to preserve the genetic material of endangered species.
But alongside these positive contributions has come widespread concern about the ethics of cloning, particularly about potential attempts to clone another human being. Many, including myself, feared that this type of technology, if left unregulated, would be misused and abused. Indeed, cloning evoked great scientific power that demanded even greater ethical responsibility, and there were no established ethical safeguards at the time to control this duty.
In retrospect, these fears have diminished in part thanks to proactive measures and the inherent complexities of the human genome (cloning an entire human being is, after all, a big leap from cloning a sheep). Importantly, the legislative and scientific communities have been resolute and unified in their opposition to the cloning of human beings.
Although a human embryo was indeed successfully cloned in 2013, no known progress has been made regarding attempts to clone a human being. Yet, Dolly’s creation technique has been widely reused and has led to many scientific innovations.
In 2003, six years after her birth, Dolly fell ill and was euthanized. His declining health was due to the development of tumors in his chest; some examinations of her cells suggested that she was also aging prematurely.
Despite her relatively short life (the average lifespan of sheep is around 10-12 years), Dolly’s influence on the scientific community was profound. Not only did it force scientists and researchers to redefine the ethics of their field, but it also laid the foundation for other important scientific advances in the rapidly evolving new field we know today as medicine. regenerative.
A powerful example is gene therapy and editing, where specific genes are targeted, edited and repaired to protect against disease, cancer, autoimmune diseases and even the rewiring of immune system cells for cancer patients. resistant to treatment. This breakthrough innovation is made possible by CRISPR technology (the same technology that enabled the rapid development of a vaccine against COVID-19), which is currently celebrating its 10th anniversary.
Genetic cloning has also been made possible thanks to Dolly. It is a type of cloning in which scientists create copies of genes in segments of DNA to combine them with plasmid DNA or self-replicating genetic material, then place this new plasmid into a host organism, such as a bacterium, yeast or mammalian cell. This process is used to develop vaccines and antigenic tests and is also used to identify useful genetic traits in plants, which can be replicated on a larger scale through genetic modification of seeds.
In addition, cloning techniques have also helped to advance agricultural practices. Farmers can use cloning technology to quickly introduce prized livestock traits (such as the ability to produce large quantities of high-quality milk) into a herd quickly through cloning and breeding. These animals will then reproduce using traditional breeding or assisted reproductive technology.
The future of cloning
Despite advances in genetic cloning and agricultural practices, cloning – especially further attempts to clone whole organisms – remains variable and highly inefficient.
Companies like Sooam Biotech Research and ViaGen Pets have successfully attempted to clone dogs and kittens for wealthy pet owners. But even today, the success rate of animal cloning is estimated at less than 30%. In fact, many animal rights activists oppose the practice citing animal welfare. In 2015, the European Union banned the practice of cloning livestock.
General interest in cloning slowed as advances in adult stem cell research gained momentum in the 2000s. This resulted primarily from the new ability of scientists to take adult human cells, for example cells cells, and reprogram them into older, more primitive, but more powerful embryonic-like pluripotent cells.
This technique was developed by Japanese scientist Shinya Yamanaka in 2006, for which he received the 2012 Nobel Prize in Physiology or Medicine. Yamanaka’s discovery of reprogramming already specialized adult cells to create “induced pluripotent stem cells” (IPS) eliminated the ethical issue of destroying embryos for research. Some scientists continue to see cloning as a way to grow genetically unique stem cells that can be used to reduce the risk of triggering an immune response.
We’ve come a long way from my exploratory journey from the Senate floor in Washington, DC, to the stand and research lab that housed Dolly in Edinburgh in 1997.
Despite all the controversy Dolly stirred up during her short life, her contributions to society were nothing short of remarkable. It has forced opinion leaders, researchers and policy makers around the world to confront the ethics of cloning. And, she encouraged us, as a society, to weigh in and engage with the ethical considerations of increasingly common scientific findings.
On all these fronts, we have worked tirelessly to instill and adhere to a strong scientific code, focusing on improving science, innovation and technology for the good of society. Cloning gave us this first glimpse of the future.
As I said on the floor of the Senate on February 3, 1998:
“This cloning debate, I think, maybe for the first time in the history of this body [the US Senate], forces us to face the inevitable as we look to the future, and it is a rapid onslaught, one after another, of new scientific technological innovations that must be assimilated into our ethical fabric. and social. Congressional Record – February 3, 1998
What I said then is still true today: “Science and ethics must go hand in hand. Congressional Record – February 11, 1998