Meselson and Stahl: The art of DNA replication

In 2003, the scientific community celebrated the 50th anniversary of James Watson and Francis Crick's landmark 1953 paper on the structure of DNA ( 1). The double helix, whose form has become the icon of biological research, was not an instant hit however. The model did not gain wide acceptance until the publication of another paper 5 years later.

Matthew Meselson and Franklin Stahl's experiments on the replication of DNA, published in PNAS in 1958 ( 2), helped cement the concept of the double helix. Meselson, a graduate student, and Stahl, a postdoctoral researcher, both at the California Institute of Technology (Pasadena), gave validity to a model that many scientists saw as speculation: how two intertwined and tangled strands of a helix could physically code for the material of inheritance. The Perspective by Philip Hanawalt of Stanford University (Stanford, CA), in this issue of PNAS ( 3), reviews the scientific Revolution of this crowning achievement and outlines its subsequent impact on four decades of DNA replication, recombination, and repair research. The two men behind the laborious steps in discovering the semiconservative replication of DNA credit much of their success to timing, hard work, and serendipity.