In her review of Anna Ziegler's play Photograph 51, Josie Glausiusz refers to DNA's “discovery” in 1953 (Nature 468, 375; 2010), when this was in fact the year its structure was solved. The molecule itself was discovered almost a century earlier.

It was a young Swiss physician, Friedrich Miescher, who stumbled on DNA in 1869, naming it nuclein. He realized that it chemically defines the nucleus — an enigmatic organelle at that time — and identified the molecule in a wide variety of cell types, including germ cells. He determined DNA's elementary composition and basic biochemical properties, and suggested that it could be important in cell proliferation, realizing it was synthesized before cell division.

Miescher developed theories on the basis of these findings to explain DNA's function in terms of fertilization and heredity, even proposing how macromolecules might encode information. His work also stimulated others to investigate DNA and its function.

Miescher should therefore be remembered not just as the discoverer of DNA, but also as the founder of molecular genetics.