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Siddhartha Mukherjee's THE GENE: AN INTIMATE HISTORY

Book review by Dennis D. McDonald

One my favorite quotations from this amazing book is this:

"In the new genomics there are very few free lunches."

By the end of this book you will understand the significance of this quotation.

The amount of information carried by the human genome is huge. When combined through reproduction with another the nature of the resulting organism is impacted by chance, multitudes of permutations and combinations, environmental factors, and a bewilderingly complex sequence of environmentally-sensitive chemically triggered processes.

The book presents a history of how humans have studied heredity and genetics. One message that comes across loud and clear is that, the more we learn about how genes operate, the more questions we seem to generate about them. Even the massive computing power we now have available can't yet resolve the many uncertainties that still exist about how genes operate and how their actions on reproduction at the sub-cellular level are controlled.

It's not just a lack of data that causes this uncertainty, it is also lack of understanding of fundamental and very complex processes. Most interesting are the author's final chapters where he discusses the potential -- and dangers --  of what we are learning.

Some diseases, for example, appear to have a very well-defined connection to specific and potentially targetable genetic code. 

In other diseases, the interaction of controls stored at many different genomic locations seem to impact disease onset in complex and incompletely understood ways. Even with basic and detailed gene sequence information in such cases, it's still impossible to predict with certainty whether a child will or will not develop one of these more complex diseases. Currently and for the foreseen future understanding and controlling how heredity, chance, and environment interact are still too complex for our complete understanding.

The author throughout the book also presents examples of how past and imperfect knowledge of genetics has been misused in cruel and horrific ways. The "eugenics" movement in the US and Germany were examples of how imperfect knowledge about heredity were used to support evil and cruel policies. 

Yet as the author plays out the amazing recent advances in genetics the ever present questions are still:

  1. How will this new and more detailed genetic information be used?

  2. Do we know enough to advise parents about the likelihood of child born of their union will have a serious disease?

  3. How does a prospective mother evaluate a report that her child will have, say, a 50-50 chance of developing a serious illness later in life?

  4. What is "normal"?

  5. Who is to decide what is normal?

This author's constant segue between a clear discussion of complex scientific topics and the implications of this knowledge for parents, the medical establishment, and society really distinguishes this book. This understanding is due in no small part to the author's own understanding of the uncertain implications of his family's history of mental illness for his own future.

In the last few chapters the implications of what we know and don't know about how genes operate in humans are discussed, even as researchers around the world rush to put this imperfect knowledge to work. At the same time governments and regulatory bodies try -- unsuccessfully in some cases -- to impose reasonable controls over experiments with human embryos.

For me a couple of things to stand out about what the author discusses.

First, pursuit of knowledge does not occur in a neat straight-line. There are human egos involved in research. Experiments often lead to surprises and unanticipated consequences. Any student of the history of science will be familiar with this. When it comes to genetics and medicine, though, the stakes surrounding these uncertainties and unknowns are high.

Second, there is no guarantee that the governance processes and institutions now in place are up to the task of providing meaningful oversight to genetic research. One reason is that genetic research isn't just about medicine and treating or preventing disease. We may soon have in our power the ability to "enhance" the human genome so that resulting individuals possess certain "desirable" or even marketable characteristics. This is a far cry from curing disease and potentially goes beyond the purposeful alteration of the human body via plastic surgery.

Third, who is to say that it is wrong to genetically modify the human species to promote specific characteristics related to size, beauty, strength, intelligence, musicality, or longevity? Aren't we just talking about the next chapter in human evolution, something societies have always supported by promoting or suppressing reproduction by selected subgroups? 

The difference now is that we know so much more than the frightening old and imperfect applications of eugenics theories about race and intelligence. What is stopping us from pursuing "more human than human"?

The author certainly makes us think about these issues.

Review copyright (c) 2017 by Dennis D. McDonald. To find out more about my consulting services go here.