The Impact of the Gene: From Mendel's Peas to Designer Babies (Paperback)

After a defence of Mendel and his contribution to biology, Tudge reviews what genes are and how they function. This in-depth overview is one of the best summations of genetic processes in print. This chapter alone is worth purchasing the book. Tudge traces the roles of DNA, RNA, the amino acids and proteins. He shows how even minuscule changes in any step in the sequence can lead to ineffective proteins. Such changes can be implemented in the development of the organism [or merely part of it] rendering it unfit to survive in its existing environment. Such change can also make the individual more fit if that environment is undergoing change. He reviews the history of discoveries concerning chromosomes, DNA [first called nuclein], enzymes and proteins. He reminds us that many of these finds were made while Mendel's work had sunk from sight. Tudge's list of the researchers involved and the dates of their discoveries is revealing for those not well-grounded in the history of biology. He shows how the many threads were brought together many years later.

Tudge addresses how the genetic ratios imply regular laws of inheritance. Tudge stresses the revolutionary aspect of this discovery and how it changed science's view of life. He notes how Mendelian genetics seemed to refute Darwin for some years. When these apparent discrepancies were later reconciled and molecular genetics arose as the science binding the two theories, limitless opportunities arose. Revelation of the DNA structure showed how genes could be identified and later used to understand their relation to the whole organism.

Tudge follows through with what has been achieved in genetic research and speculates on what the future might hold. He pulls no punches in his speculations and readers will be confronted with myriad possibilities. These shouldn't be discounted nor blithely cast aside as distasteful. His proposals are realistic and based on strong science.

This book should stand as Tudge's finest effort. He's written many books on science, with some focus on human evolution. Standing as a pinnacle among his publications, readers are urged to take up this volume intending to give it a careful read. His Epilogue carefully reviews the many ethical questions that arise from the new power that genetics has placed in our hands. He reminds us of the pitfalls that have been encountered in the past and to prepare for these in decision-making. Public policies, which ultimately rest in your hands, he reminds us, must be formulated on a basis of clear understanding of what is involved.
This book provides an excellent starting point for building that knowledge base. He warns us against letting events overtake us. Read him to stay abreast of what is transpiring. [stephen a. haines - Ottawa, Canada]