ABSTRACT
The introduction reveals how DNA transmits hereditary information from one generation to another. The reasons are given as to why DNA was dismissed as the material of genes despite evidence from studies on cell division and examples from the work of Morgan on Drosophila and that of Avery on pneumococcus. The Watson-Crick DNA model is described along with earlier structures based on the Levene tetranucleotide hypothesis and the Pauling triple helix. Here, I relate how the correct structure led to the discovery of the genetic code that connects DNA sequence to protein amino acids and how the study of bacterial genetics shaped our initial understanding of gene expression.. The discovery of reverse transcriptase, by Howard Tenim and David Baltimore, which viruses use to copy RNA into DNA, led to new insights into how metazoan genomes evolve. The surprise caused by thediscovery of split genes in more complex genomes by Phil Sharp and Rich Roberts is described, and how this finding contibuted to the idea that much of these genomes consisted of “junk” sequences. It is in the junk where the flipons are to be found.
