Werner Arber on Genetic Variation
  Werner Arber     Biography    
Recorded: 08 May 2012

Yes, well in fact I can tell you two things. One is, having been aware in my PhD study already, as I mentioned, that viruses can serve as gene vectors, carrying some genes from type of bacteria to another bacteria. For example, galactose fermentation genes. And we could show that—I mean, it was becoming clear, more and more, that other segments of the genome also can be carried around occasionally by viruses as gene vectors. So, I got aware of the horizontal transfer and it became more and more clear to me that restriction is a defense against accepting foreign DNA, because often if you accept too foreign genetic information the harmony of the cell may be destroyed. And, on the other hand, this knowledge that viruses can serve as gene vectors, and sometimes often that is hybridizing between host DNA and fully viral DNA, which is still able to replicate. People felt that this is a way to sort out genes from very large genomes. To study it finally. And, actually some people started to, by sheer force, break the DNA into small fragments, integrating them into viral gene vectors. And it worked. But, that was kind of very difficult to sort out. When the restriction enzyme became available around 1970, all of a sudden that was very simple. You take that large chromosome, you break it into fragments, the fragments can be separated by, you sort out a particular segment, and put it in a gene vector. Grow it on its own. So that actually was the start of these molecular genetics, which later on led to genomics.

Werner Arber, (born June 3, 1929, Gränichen, Switz.), Swiss microbiologist, corecipient with Daniel Nathans and Hamilton Othanel Smith of the United States of the Nobel Prize for Physiology or Medicine for 1978. All three were cited for their work in molecular genetics, specifically the discovery and application of enzymes that break the giant molecules of deoxyribonucleic acid (DNA) into manageable pieces, small enough to be separated for individual study but large enough to retain bits of the genetic information inherent in the sequence of units that make up the original substance. Arber studied at the Swiss Federal Institute of Technology in Zürich, the University of Geneva, and the University of Southern California. He served on the faculty at Geneva from 1960 to 1970, when he became professor of microbiology at the University of Basel. During the late 1950s and early ’60s Arber and several others extended the work of an earlier Nobel laureate, Salvador Luria, who had observed that bacteriophages (viruses that infect bacteria) not only induce hereditary mutations in their bacterial hosts but at the same time undergo hereditary mutations themselves. Arber’s research was concentrated on the action of protective enzymes present in the bacteria, which modify the DNA of the infecting virus—e.g., the restriction enzyme, so-called for its ability to restrict the growth of the bacteriophage by cutting the molecule of its DNA to pieces.