DNA: Watson Speaks His Mind

This is a review of the book DNA: The Story of the Genetic Revolution by James Watson with Andrew Berry and Kevin Davies. When I saw the 2017 copyright under Watson's name the first question that came to mind was if he is still alive, given his Nobel-prize winning co-discovery of the structure of the DNA molecule was quite a while ago (1953). Watson is actually alive and 94.

As a physicist with almost no knowledge of biology, I found this book extensive, accessible, and fascinating.

1. Background: This is a quick recap of the basic biology I seemed to require for launching into the book: cells contain nuclei, which contain chromosomes, which are strands of DNA. Sections of a DNA strand constitute genes. There is ongoing debate about function of the material in between the genes - sometimes it is called junk DNA, sometimes dark matter.

2. Prehistory: The book begins by reminding us that humankind has been running genetics experiments for many thousands of years by breeding plants and animals; and by tracking the hereditary transmission of diseases.

3. History: Modern genetics proper starts with Mendel's paper in 1866, followed by Walter Sutton's indication of the role of chromosomes, and then the monumental work of T.H. Morgan on fruitflies at Columbia, where he observed gene recombination via separation of linked traits.

   The book then discusses Galton (who pushed eugenics), Goddard (who introduced IQ tests to the US from Europe) and Madison Grant (whose book on racial eugenicist policies was declared by Hitler to be his bible.)

4. DNA: Watson describes his undergraduate days at University of Chicago and the influence of What is Life?, the book in which Schrodinger suggested life could be understood in terms of transmission of genetic information. The chapter condenses the story of the discovery, by Watson and Crick, of the structure of DNA, and told earlier and in more detail in The Double Helix.

Much of the rest of the book is about advances in the study of genes.

5. Genes produce enzymes: This was established by the pioneering experiments of Beadle

and Tatum on mold.

6. Genes produce proteins: (Not all proteins are enzymes). This was established by Francis Crick, involved an understanding of RNA as the intermediary, and is now known as the Central Dogma of Molecular Biology.

7. Genes express themselves: Genes switch on at different times and in different cells so an entire organism (e.g. a human) can develop from a single cell (the fertilized egg for humans). These studies were started by Jacob, Monod and Lwoff, followed by many other researchers.

8. Recombinant DNA: The story moves on to the development of cutting (e.g. with

restriction enzymes), copying (e.g. with polymerase chain reactions) and pasting (e.g.

with DNA ligase) sections of DNA (e.g. genes).

These were seminal advances, eventually giving rise to the field of biotechnology

evolving into powerful technologies like CRISPR (Clustered Regularly Interspaced Short

Palindromic Repeats) which can edit the genes of living organisms.

9. Biotechnology: Human genes were harvested to produce valuable proteins such as insulin (related to the start of Genentech, the world's first biotech company), tPA (used for treating strokes), and bovine growth hormone (which gives more milk yield), etc. The book naturally moves on to GMOs (genetically modified organisms) such as crop plants with better pest resistance.

10. Human Genome Project: A big movement was the sequencing of the human genome (complete set of genes) which was completed in 2003. This involved personalities like Bill Clinton, Watson himself, and Craig Venter (who started Celera Genomics).

11. Genes and disease: The ability to sequence our genomes allows us to identify which diseases our genes predispose us to (e.g. APOE on chromosome 19, which correlates with Alzheimer's). Not unexpectedly, the search for cancer cures has dominated the biotech industry, focusing on genes which mutate to cause cancer (oncogenes); the book devotes an entire chapter to this topic.

12. Genes and our Past: DNA contains information allowing us to identify species (Neanderthals vs. humans; an interesting gene in this context is FOXP2, which affects speech), our ancestry (this is molecular anthropology; some amusing paternity suits are mentioned in the book, as well as the company Ancestry.com), and the traces we leave behind at historical or crime scenes (some sensational cases are included).

    
    

    Some trivia collected from the book:

    
    

    African elephants stay fertile until they die (~90 years); human chromosomes are numbered in order of decreasing size (chromosome 1 is the largest, with a quarter billion base pairs), except for the sex chromosomes which are labeled X or Y; the mustard plant has more genes (27,000) than us (21,000); cytogenetics is the study of chromosomes; the Flynn effect says worldwide IQ is increasing.

    
    

    Summary

    
    

    The material is well arranged, the writing is taut, the technicalities are explained well. Watson has been reasonably frank about his opinions on politics, religion, eugenics and the future of biotechnology. His panoramic view of the field is impressive.

    
    

    I would say this book is a resource for a nonexpert in biology (like me) as a useful introduction to as well as survey of a fundamental, vast and profound field of scientific research which is indubitably going to affect our lives in the past (ancestry), present (healthcare), as well as the future (longevity).