32 questions · 13 almanac · 0 findings

Genetic Engineering and Recombinant DNA

Techniques for directly modifying organisms' genomes.

Almanac Molecular Scissors, Molecular Glue
  • What do restriction enzymes do in bacteria naturally, before Berg's lab repurposed them as a tool?
  • How did Paul Berg's lab combine restriction enzymes and ligase to construct the first recombinant DNA molecule?
  • What did Boyer and Cohen demonstrate in 1973 by inserting a foreign gene into E. coli?
Almanac A Borrowed Gene, Passed to the Next Generation
  • What role do restriction enzymes and DNA ligase play in splicing genes from two different plasmids?
  • How did Boyer and Cohen prove that the recombinant plasmid was faithfully copied by E. coli's descendants?
  • What industry grew out of the 1973 Boyer-Cohen experiment, and what was its first major medical product?
  • How were diabetics treated with insulin before recombinant bacterial production became possible?
Almanac An Hour in a Bar Started an Industry
  • How did a cold call from Robert Swanson to Herbert Boyer in 1976 lead to the founding of Genentech?
  • What earlier discovery by Boyer and Stanley Cohen made a company like Genentech possible?
  • Why was Genentech's production of somatostatin in bacteria such an important proof of concept?
  • How did Genentech's early work lead to the production of human insulin and growth hormone soon after?
Almanac Bacteria Had Been Editing DNA All Along
  • Why do bacteria have enzymes that cut up viral DNA at specific sites in the first place?
  • What was the difference between Werner Arber's theoretical prediction and Hamilton Smith's isolation of an actual restriction enzyme?
  • How did Daniel Nathans use restriction enzymes to build the first genetic map of a DNA molecule?
  • How did the discovery of restriction enzymes lead directly to recombinant DNA technology?
Almanac Reading the Code, Letter by Letter
  • What did Paul Berg demonstrate about cutting and rejoining DNA from different organisms, and why was that considered opening a door?
Almanac A Tomato Bred to Stay Ripe Longer
  • Why are standard commercial tomatoes harvested green and then gassed with ethylene?
  • How did inserting an antisense gene targeting polygalacturonase slow the Flavr Savr tomato's softening?
  • Why did the Flavr Savr fail commercially despite being the first genetically modified whole food approved by the FDA?
Almanac Any Gene, Chosen and Silenced
  • How did Capecchi and Smithies use the cell's own homologous recombination machinery to knock out a specific gene?
  • What role did Martin Evans's embryonic stem cell lines play in creating knockout mice?
  • Why did the Nobel committee award the same trio for the same discovery six years after the Lasker?
Almanac A Mouse Missing One Gene on Purpose
  • What is homologous recombination and how did Capecchi and Smithies use it to alter genes?
  • What did Martin Evans discover about culturing mouse embryonic stem cells?
  • How does a knockout mouse let researchers determine what a single gene does?
Almanac Three Molecules Fix a Misfolded Channel
  • What does the CFTR gene normally do, and how does the F508del mutation disrupt it?
  • How do the three molecules in elexacaftor–tezacaftor–ivacaftor each address a different step of the CFTR defect?
  • What fraction of cystic fibrosis patients benefited from this triple combination therapy?