The Evolving Story of DNA, Genes, and Genomes

Last year, 2023, was the 70th anniversary of the discovery of the structure of DNA by Watson and Crick. In those 70 years, there has been an amazing growth in the knowledge of the biology of DNA; as chemistry, biochemistry, and molecular biology, cell biology, genetics, physics, and bioinformatics have been brought to bear. The central dogma of DNA → mRNA →protein has been refined. Restriction enzymes for cutting DNA at specific sites led to recombinant DNA and the cloning of individual genes. The interrupted eukaryotic gene is organized into exons and introns, with the introns being spliced out. Discovery of DNA sequencing led to the human genome project. This was followed by new-generation sequencing technology and the explosion of genome sequencing. The human genome sequencing has revealed that the human genome has much more than individual protein-coding genes. Noncoding RNA genes have been revealed. The role of nucleosomes in the organization of the genome has been refined. Much DNA in the nucleus is devoted to how genes are regulated leading to the development of human complexity.