DNA HelixDNA, and its oxidized counterpart, RNA, are the fundamental molecules of all living organisms. The fascinating thing about life is that, elementally, it is almost all identical; the same 6 elements (carbon, hydrogen, nitrogen, oxygen, phosphorous, and sulfur — CHNOPS) comprise over 99% of the weight of living matter. Indeed, the only reason that a lizard is a lizard and a human, a human is due to the different instruction set coded into DNA. James Watson and Francis Crick, two young molecular biologists at the time, published their seminal findings on the structure of DNA in the journal Nature in 1953. The piece was entitled, “A structure for deoxyribose nucleic acid.” The article was a mere 3 pages long, but it was undoubtedly one of the most significant scientific advances of the 20th century, as it would change the way we understood how living creatures procreate and differentiate, at both the cellular and organismal levels.

While the paper dealt uniquely with proposing a structure for the molecule, Watson and Crick subtlety hint at the obvious magnitude of their discovery in one of the concluding paragraphs:

It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material.

The “pairing” they refer to is the central dogma of the nitrogenous base hydrogen-bonding preferences: adenine bonds to thymine, and guanine to cytosine. Within that simple code of A-T|C-G arise the instructions for the arrangement of every organ, tissue, cell and molecule in complex lifeforms, similar to the way computers use a binary of 1s and 0s to perform exceedingly complex tasks. Watson and Crick had peered into the biological foundation of life, and the rest is history. I highly encourage you to read their original article.