Review: Neanderthal Man by Svante Pääbo

Svante Pääbo is the winner of the 2022 Nobel Prize in Medicine and Physiology for the work described in this book. As a student in Sweden Pääbo conceived the dream of decoding the genome of ancient humans and Neandertal Man. This book is the story of that dream, that quest, and all that went into building the scientific institute and international collaboration that achieved that goal thirty years later.

Like James Watson’s famous book The Double Helix, this is an inside look at how molecular biology is done at the very highest level. Much has changed in biology in the half century plus between these accomplishments and much has stayed the same, but for anyone who wants to know how science really works, here is the story, laid out in compelling detail. We also get a detailed look at the personal life of the author.

Pääbo’s thirty year dream culminated in the publication of the Neandertal genome. So what did it take to achieve it?

When the author began his quest, methods for sequencing DNA were difficult and laborious. One of Pääbo’s early triumphs was persuading the Max Planck Society to set up The Max Planck Institute for Evolutionary Anthropology dedicated to his quest. Of course this was only possible because he had already demonstrated his talent and scientific bona fides.

Despite the story told in Jurassic Park, finding and sequencing ancient DNA is extremely difficult. The problem is that DNA is a fragile molecule. In our bodies It is carefully cared for and repaired. Failure of the repair mechanisms often results in cancer. Once the owner of the DNA dies, most DNA very quickly disintegrates. Its enemies are manifold: heat, moisture, environmental radiation, and bacteria.

If you are extremely lucky and have an old bone that has been reserved in cold dry conditions, you might find some DNA. That DNA will consist not of whole chromosomes but of small fragments. I believe that the first ancient DNA reconstructed came from a frozen Siberian mammoth. Among the many challenges of decoding ancient DNA one of the worst is contamination. If you extract DNA from an old bone most of the DNA will bacterial, human (from the humans who have found or otherwise handled the bone) or other from miscellaneous sources. Despite elaborate clean room technology for handling the material, much of the contamination was already in the material.

Bacterial DNA is different enough that sequencing can quickly identify bacterial DNA fragments, but how do you pick out the mammoth DNA? Well, you compare it with relatively close relatives, modern elephants.

Where Watson and Cricks DNA structure discovery was mostly a matter of a very few individuals working in relative isolation, Pääbo’s Neandertal work was based on a he global collaboration that he put together. Molecular biologists from many countries, archaeologists from Croatia and Russia, inventors and sequencing companies from the US and Britain all made essential contributions. That aspect of the work is the way modern big science now often must work. Of course Pääbo alone got the Nobel but I suppose that is also modern – the rewards for the work of hundreds sometimes goes to one or a few – but it was his dream, his project, and the collaboration he built.

I found it a very good read, and I strongly recommend it to those with an interest in molecular biology or ancient DNA. I believe that most of it is also accessible to the interested and informed public.

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