Friedrich Miescher isolates DNA for the first time.

Miescher, a Swiss scientist, wanted to study the chemistry of cells. He chose to study white blood cells, which are abundant in pus, and were abundantly available to him in bandages from a hospital near his university. Miescher isolated a material rich in phosphorus from the cells and called it nuclein. He found nuclein in other types of cells as well, including salmon sperm.

In the early 1900s, other scientists began to describe the chemical properties of DNA in much more detail.