When was the theory of RNA announced?
Nirenberg and Matthaei experiment
In August 1961, at the International Congress of Biochemistry in Moscow, Nirenberg presented his paper. The experimentation with synthetic RNA in a cell-free system was a key technical innovation. In 1961, when they announced their methods for decoding the relationship of mRNA to amino acids, there was still a lot of experimentation required before the entire code was deciphered. The scientists had to determine which bases made up each codon, then determine the sequence of bases in the codons. This proved to be a tremendous amount of work.
History of RNA biology
When first studied in the early 1900s, the chemical and biological differences between RNA and DNA were not apparent, and they were named after the materials from which they were isolated; RNA was initially known as "yeast nucleic acid" and DNA was "thymus nucleic acid". Using diagnostic chemical tests, carbohydrate chemists showed that the two nucleic acids contained different sugars, whereupon the common name for RNA became "ribose nucleic acid". Other early biochemical studies showed that RNA was readily broken down at high pH, while DNA was stable (although denatured) in alkali. Nucleoside composition analysis showed first that RNA contained similar nucleobases to DNA, with uracil instead of thymine, and that RNA contained a number of minor nucleobase components, e.g. small amounts of pseudouridine and dimethylguanine.