Early breakthroughs

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One of the things driving biology is the development of new technologies. The real breakthroughs and revolutions in science have occurred in part because of the development of technologies but also, of course, the introduction of new ideas – such as Darwin’s insights into the origins of species and natural selection.

One of the first really important DNA technologies was the ability to make recombinant DNA. This was done by Paul Berg and then Boyer and Cohen out in San Francisco and at Stanford University in the early 1970s, while I was still an undergraduate. It was a very exciting time in biology and induced me to study molecular biology. The ability to take DNA from one species and clone it into bacteria really set the scene for the beginnings of the modern era of molecular biology.

From the laboratory to the courtroom

A number of laboratories, and particularly Fred Sanger’s at Cambridge University, developed techniques for sequencing DNA very rapidly. So, we go from 1977, when we were sequencing the very small pieces of DNA that determine the sequence of the base pairs, to the present day, when we can sequence an entire human genome in a single day for about a thousand dollars – which is really quite extraordinary.

Another technology that appeared somewhat later was the polymerase chain reaction. This uses the DNA polymerases that normally copy the genomes of cells, but you can use them in a test tube to make many millions of copies of DNA from a single molecule. You can take a single molecule of DNA and then amplify it using this polymerase chain reaction. It’s effectively DNA replication on steroids, but DNA replication of a very focused segment, as determined by the experimenter.

This PCR technology has been extremely important for society. It’s used not only for medicine and biological research but also for forensic evidence in court cases. It can show that people are guilty. It can also prove that people who were convicted of serious crimes did not, in fact, commit those crimes, and were condemned due to false testimony in their original trial.

The gene-editing revolution

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Moving a long way forward, another revolutionary technology appeared in 2012: what we now call gene editing. Gene editing actually existed before 2012, but the important breakthrough was the discovery of how a complex called CRISPR/Cas9 can be used to edit the genomes of cells. This was done by a number of people, but particularly Jennifer Doudna and Emmanuelle Charpentier, who won the Nobel Prize in 2020 for their work.

This has already had an enormous impact in biology. We use CRISPR/Cas9 genome editing in my laboratory all the time to make specific gene mutations.

This discovery, like the ability to clone DNA from a human and put human genes into bacteria, caused controversies. Indeed, when recombinant DNA was first used, scientists put a temporary moratorium on it while they thought through the ethical implications of this technology. Eventually they came to the conclusion that there was no real risk in recombinant DNA. In fact, there have been no serious or even non-serious side effects of recombinant DNA that I can think of, but there have been enormous benefits: the ability to make recombinant insulin for diabetics, recombinant growth hormone for people with growth deficiencies and monoclonal antibodies that can treat a vast array of diseases. All of these come from recombinant DNA.

Ethical dilemmas of DNA technology

From the beginning, scientists have been attuned to the ethical dilemmas of technologies such as recombinant DNA. When CRISPR/Cas9 emerged, there was an immediate recognition by the scientific community that this could raise serious ethical questions. These questions have been addressed not only by the scientific community but also by broader society, which is how it should be.

One important issue is the fact that, using CRISPR/Cas9, we can design a mutation at will and put it into a particular species, be it plant or animal. This technology has been enormously valuable. It’s been used, for example, to increase fruit yield in plants, and it’s something that my colleagues at Cold Spring Harbor Laboratory are doing all the time.

It bypasses the manual human selection of natural mutations that occur in the vast array of fruits and plants in the environment. Over the many thousands of years that humans have been engaged in agriculture, breeders have been able to select traits that increase fruit yield, fruit size or crop yield. Nowadays, we can go in and precisely change a specific gene to increase fruit yield, without relying on the randomness of all the mutations that exist in plants or animals.

Most scientists, myself included, would agree that using CRISPR/Cas9 to modify the DNA inside the adult cells of our body, the so-called somatic cells, to correct a mutation and potentially reverse a serious disease is entirely ethical. We’re using this technology right now.

The ethical dilemma arises when you go into the germ line – the cells that produce either eggs or sperm – and modify its DNA, which can be inherited forever across generations of people. Most scientists, myself included, do not support changing the germ-line DNA.

Educating the next generation

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One of the interesting things about the development of technologies is that, in general, scientists immediately recognise any ethical problems associated with said technologies. This is true for medicine and biology but also in fields such as nuclear physics.

It’s not enough for scientists to recognise these problems, which we do. We also need to let the wider public know what the technology is, what it can do and also any ethical dilemmas that arise from it.

Ultimately, it is society that needs to decide how technologies should be employed. This is tricky, however, because these are very complicated technologies and there’s a lot of false information out there, particularly in the age of social media and the internet. People may read false information online and get the impression that some technologies are actually more dangerous than they are. It’s incumbent upon scientists to inform and educate the public. It’s one of the most important responsibilities we have.

At Cold Spring Harbor Laboratory, we have a very large public education outreach programme. We started what we call the DNA Learning Centers, which on Long Island alone teach 32,000 middle and high school children about laboratory-based DNA technologies, including CRISPR/Cas9. The vast majority of these children are not going to grow up to be scientists; however, we want them to grow up to understand the technology, so that when they participate, which I hope they do, in the societal discussions about how to use these technologies, they’ll be better informed.

Bringing science into politics

We now have DNA Learning Centers around the world, including in Australia, China, Europe, Singapore and throughout the United States. We’re trying to bridge a gap in public education. Our philosophy is that if you catch the children in middle and high school and not just select those who are interested in science, then you’re going to have generations of people growing up with an understanding of science and its associated technologies.

Another interesting thing is the scientific process itself, the way we go about doing science on a day-to-day basis. Scientists have to look at data, interpret it and come up with new ideas, interpretations and theories. The data gives us a path to follow.

Using data and logical thinking is actually a very good way to make decisions in society. So, another thing that scientists should do is transmit this logic and scientific way of thinking to society, which I think will counter a lot of the misinformation and rather kooky ideas that occur – as well as some decisions made by politicians, which we really can’t understand. If they use the scientific method to make decisions, that could improve society enormously.

Discover more about

The uses and implications of DNA technology

Stillman, B. (1996). Cell Cycle Control of DNA Replication. Science, 274(5293), 1659–1663.

Stillman, B. (2000). "Director's Report". Cold Spring Harbor Laboratory 2000 Annual Report, 1–7.

Greider, C.W., Sheltzer, J.M., Cantulopo, N.C., et al. (2019). Increasing gender diversity in the STEM research workforce. Science 366(6466) 692–695.