When you ask laypeople to describe a gene and its function, you will likely get a variety of responses. They have heard of genes and may be aware that they are found in cells and involved in the passage of traits from parents to offspring. They might even say a gene has DNA that carries such traits as skin and eye color, height, diseases, and a person's sex. And some may have ideas that genes carry baseball ability, spelling skills, or even a person's nationality. But the structure and processes of genes are not known to many. This book can help get the message across with its detailed analysis of the concept and nature of the gene through much of the past two centuries. The authors compare the work, and the frequently opposing viewpoints, of numerous scientists who sought to understand and solve the mystery of inheritance in living organisms.

Beginning with the nineteenth century, the narrative follows the history of ideas, experiments, theories, and conclusions of many scientists as the knowledge and characterization of the gene is developed. From a time when scientists were mostly concerned about what produced single individuals, they began to recognize that traits in offspring could be transmitted from both parents, as well as from ancestors. It was clear that some sort of biological heirloom was being passed down through generations. Gregor Mendel's conclusions from his well-known experiments with peas were ignored for many years, but later they became the basis of a new scientific discipline named genetics by English biologist William Bateson. Mendel had realized that there was some kind of “factor” responsible for the transmission of traits, but it was Wilhelm Johannsen who coined the word gene to describe Mendel's “factors.” Genetics gained more widespread interest in the early twentieth century as agriculture and medicine found new support for animal and plant breeding and the hope of finding new ways for fighting diseases. Geneticists eventually came to believe that genes were physical units that lined up on chromosomes.

Near the mid-twentieth century, many scientists felt that proteins were probably the genetic material, but it wasn't long before nucleic acids were considered. By then, scientists were using bacteria for genetic research, since they could follow the inheritance process over many generations in just a few days. When it was found that DNA from a pathogenic bacterial strain could be transferred to a harmless strain, causing its descendants to be infectious, this showed that DNA was involved in heredity. When Watson and Crick published their paper on the configuration of DNA, they noted that their proposed structure actually supported a possible copying mechanism for genetic material. This led to the unlocking of the genetic code and the realization that its replication, transcription, and translation were the same for all organisms.

With the appearance of gene technology, the gene concept became that of an entity that was interchangeable and could be manipulated. New discoveries – with new names such as polymerase, reverse transcription, ligase, plasmids, and many others – led to the development of new biological and medical efforts that included engineered bacteria that could digest oil residues or mass produce human insulin. Eventually it became obvious that the disciplines of genetics, developmental biology, and evolution were intertwined. A detailed analysis shows how the gene concept continued to transform into complex systems that made evolution possible even as they were and are subject to shuffling and reshuffling. Some research has even suggested that there may be more genetic systems involved in development and evolution (developmental systems theory). Heading into the future, it becomes clear that there are still unknowns, that not all parts of genomes are necessarily codes for essential functions, and that understanding the gene concept is still a work in progress. As the authors conclude, “Only time will tell what life is like.”

There is far more to be found in this intriguing volume. With 120 pages of text, an extensive bibliography, and an index of names, The Gene is a brief book but not a quick read. An intense vocabulary level makes it seem like a highly complex article for a professional scientific journal. It is fascinating, extensively researched and cited, well crafted, and doesn't miss much in its sometimes dizzying array of back-and-forth explorations, ideas, and complex explanations from the variety of scientists followed in the narrative. It would be a valuable resource for college biology students, particularly those in upper-level genetics or evolution classes. Biology teachers at the college and even the high school level will find it useful for background.

Richard Lord

Retired Biology Teacher

Presque Isle High School

Presque Isle, ME 04769

rnlord@aol.com