February 28, 1953: Chemical Structure of DNA Was First Discovered
Nowadays, the structure of DNA is well-known for life science researc, and even the general public are familiar with it. Nevertheless, have you thought of who discovered the secret of life in the first place? On February 28, 1953, American molecular biologist James D. Watson and British biologist Francis H.C. Crick announced that they have determined the double-helix structure of DNA.
Reference
http://www.history.com/this-day-in-history/watson-and-crick-discover-chemical-structure-of-dna
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http://all-len-all.com/on-this-day-april-25-1953-watson-and-crick-propose-double-helix-dna-structure/