This tome’s subtitle describes it better than its title. It is a history, not a book on genetics per se. The author describes how genetics emerged as a science with experimenters like Mendel and his pea plants and finishes up with the latest developments in gene splicing with the CRISPR tool. The writing is clear, easy-to-understand (at least for the relatively well-read with a biology class or two), and well-researched. There is quite a bit of repetition, so the reader can skip liberally, which is probably necessary for most people since it is a very long book. I think it was about halfway through the book before researchers even recognized the concept of a gene. If you are interested in the subject but want a deeper understanding of what’s happening today in gene research, I recommend Jennifer Doudna’s A Crack in Creation: Gene Editing and the Unthinkable Power to Control Evolution which is more up-to-date but also more technical.
This is not a medical book, nor is it in any way related to ancestry or genealogy. To be sure, it does mention many gene-related diseases and some progress (or setbacks) in the area of gene therapy, but that is a relatively small part of the book. It does not explain how genome companies like 23andMe or Ancestry.com determine your ethnic ancestry from your genes. It is, however a broad treatment of the history of genetics research and discovery and well-written. I take some issue with the author’s final conclusions. I believe he has inserted his own moral judgments rather liberally into what he calls the “scientific, philosophical, and moral lessons of this history.” For example, his lesson 9 says every genetic “illness” is a mismatch between an organism’s genome and its environment. In other words, every such illness is, or would be, actually of benefit in some other environment. I disagree. That may be true of some diseases such as sickle-cell disease, which is harmful, but the sickle-cell trait (conferred when only one parent provides the gene) provides some protection against malaria which is no doubt why it hasn’t been expunged through natural selection. But there are other genetic diseases that confer no benefit. The child is born with horrible mutations that lead rapidly to a painful death. Some diseases are simply genetic mistakes.