About Erwin Chargaff
He died in New York City on June 20, 2002. He was 96 years old.
His second discovery was that the composition of DNA varies from one species to another, also known as Chagaff's Rules.
His research helped lay the groundwork for James Watson and Francis Crick's discovery of the double-helix structure of DNA. In 1952, he sat down and discussed his results with the two. They helped him figure out the reason for the regularity with the bases, which he failed to notice before.