DNA and the Rise of Modern Biotechnology

Biotechnology utilizes microorganisms, plant, and animal cells to produce industrial products, therapeutic proteins, and research tools. It also includes gene therapy and genetic engineering. Traditionally, biotechnology products include alcoholic beverages such as wine and beer involving fermentation driven by yeast, cheese using bacteria, and bread using yeast. Modern biotechnology is associated with the understanding of the structure of DNA, its replication and translation, the proteins produced, and the way DNA can be manipulated. The beginning of modern biotechnology was the cloning of a piece of DNA cut with restriction enzymes and spliced into plasmids in E. coli in 1973. This cloning technique led to the production of human insulin and human growth hormone, followed by other therapeutic proteins. New techniques allowed the discovery and isolation of specific genes of interest. Techniques included nucleic acid hybridization, the reverse transcriptase enzyme (RNA→DNA), the polymerase chain reaction (PCR), and continued improvements in sequencing. The development of the US National Center for Biotechnology Information (NCBI) database was central to gene discovery and continues to have an important role. The discovery and cloning of the BREAST CANCER GENE 1 (BRCA1) was an important step in the isolation of diverse genes. The completion of the draft DNA sequence of the human genome in 2001 marked an important milestone. The development of new-generation sequencing led to the sequencing of the genome of many organisms and the routine sequencing of human genomes for genetic analysis. For human gene therapy, it was necessary to develop suitable vectors. Replication-deficient recombinant adenovirus that enters the nucleus and is not integrated into the genome and adeno-associated virus vectors (AAV) is discussed. Genetic engineering (GE) of plants involving gene insertion is possible using Agrobacterium tumefaciens-based vectors. GE cattle produced by somatic cell nuclear transfer (SCNT) have become part of breeding strategies.