From the Gene to Metagenomics: The Frontiers of Molecular Biology

Abstract

AbstractThis chapter will begin by examining Mendel’s research on biological heredity and his theory that hereditary elements are passed on through discrete units. This idea would eventually lead to the discovery of DNA. Mendel’s formulation of the laws governing the transmission of characteristics from one generation to the next constituted a fundamental conceptual evolution in biology. Mendel’s ideas were also fundamental in the process that led to the molecularization of biology. After the 20th-century rediscovery of Mendel’s work, biologists identified and determined the structure of the molecule responsible for storing and passing on genetic information. This molecule is DNA, and the information that it carries is closely related to its molecular structure. Hence, the chapter traces the historical and philosophical development that led from the unit of heredity to the concept of the gene, to its molecularization in DNA, and to the latest developments in epigenetics and metagenomics. Particular focus is placed on DNA because this concept has transcended its strictly scientific role. Because this molecule is the seat of the identity not only of all living beings but also of all biological species, DNA represents both a medical resource and the possibility of genetic manipulation to selectively “improve” the human genome. These abilities to manipulate DNA have given rise to a great deal of philosophical debate and a wide range of ethical concerns about genetics.