Paul Berg

Who Joined Two Genomes, Then Called a Halt · Biochemist · 1926–2023

The biochemist who built the first molecule of DNA containing genes from two different organisms — and who then organised the scientific community to restrain itself before the technique was used.

Who was Berg?

Paul Berg was born in Brooklyn in 1926 and spent his career at Stanford. In 1972 his laboratory achieved what became the founding act of genetic engineering: DNA from the monkey virus SV40 was joined to DNA from a bacterial virus, producing a single molecule carrying genes from two organisms that had never exchanged genetic material. The obvious next experiment was to introduce that molecule into Escherichia coli, a bacterium of the human gut, so that it would be copied indefinitely. Berg did not do it. A colleague, Robert Pollack, telephoned to say the experiment alarmed him, and Berg concluded that nobody could say what a tumour-virus gene loose in a gut bacterium would do. In 1974 he and ten colleagues published a letter in Science calling for a voluntary international moratorium on certain classes of recombinant experiment. In February 1975 he chaired the Asilomar conference in California, where about 140 scientists, together with lawyers and journalists, spent four days negotiating containment guidelines for their own field — an almost unprecedented act of self-regulation, and one that has been criticised ever since for being scientists judging themselves. He shared the 1980 Nobel Prize in Chemistry with Walter Gilbert and Frederick Sanger.

Major achievements

• Constructed the first recombinant DNA molecule, joining genes from two organisms (1972)
• Chose not to perform the follow-up experiment on safety grounds
• Co-authored the 1974 Science letter calling for a moratorium on certain recombinant work
• Chaired the 1975 Asilomar conference, which produced containment guidelines for the field
• Shared the 1980 Nobel Prize in Chemistry for work on the biochemistry of nucleic acids

Life in brief

• 1926 — Born in Brooklyn: Educated at Penn State and Western Reserve.
• 1959 — Joins Stanford: Begins work on the biochemistry of nucleic acids.
• 1972 — The first recombinant DNA: SV40 DNA joined to bacterial viral DNA in one molecule.
• 1972 — The experiment not done: Halts the plan to put the molecule into gut bacteria.
• 1974 — The moratorium letter: Eleven scientists ask the world's laboratories to pause.
• 1975 — Asilomar: Chairs four days of argument that produce containment rules.
• 1980 — Nobel Prize in Chemistry: Shared with Walter Gilbert and Frederick Sanger.
• 2023 — Dies: Fifty years after the molecule that began the industry.

Explore the life of Berg — five chapters

1. A Brooklyn Science Club — A teacher who let students find things out
2. The Tools Came From Bacteria — Restriction enzymes, ligase, and what made it possible
3. The Experiment He Did Not Do — A telephone call from Cold Spring Harbor
4. Asilomar — Four days in February 1975
5. What Followed — An industry, a Nobel Prize, and a reference point

Read the five-chapter life of Paul Berg →

Where Berg appears in your course

Paul Berg has a genuine claim on 1 lesson of the Pearson Edexcel International GCSE science course built into Incandio:

• Genetic Engineering — Biology: In 1972 Berg's laboratory joined DNA from a monkey virus to DNA from a bacterial virus, making the first molecule to contain genes from two different organisms — the act this whole page describes. The obvious next step was to put it into the gut bacterium Escherichia coli, and he did not do it, because a colleague telephoned to say that nobody could predict what a tumour-virus gene would do loose in a bacterium that lives in people. He called for a worldwide pause instead, and chaired the 1975 conference that wrote the field's own safety rules.

Begin

• Start a conversation with Berg — a dramatised, historically grounded AI portrayal
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• Explore the life of Berg — five chapters
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