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3 of 3 people found the following review helpful:
5.0 out of 5 stars
Makes a very long story short, 18 Jul 2005
Since the announcement of the coarse mapping of the human genome, the media have deluged us with promises of great advances. Medicine, agriculture, psychology, even biotechnology, all seem to be potential beneficiaries of the the unravelling of "what makes us human". Henry Gee, in presenting a sweeping background to these attractive promises, sounds a cautionary note. How is it, he asks, that from the moment of conception a process is unleashed that produces a living child in a mere 200 days? From the merging of two single cells, each carrying their share of the information that built you and i, what led to each of us being distinct individuals, yet bearing an inheritance reaching billions of years back in time?Although the event is common, with 150 human births occuring every minute, Gee explains that understanding of the process was long in coming. From Aristotle, who thought babies came from menstrual blood to the Enlightenment, which accorded either eggs or sperm with possession of generations of nested individuals, there was a long, tortuous path to understanding conception. Behind that understanding lay much investigation, theorisation and speculation. Gee naturally positions Charles Darwin with a pivotal role in that understanding, but wants us to be aware of the host of other researchers and their contributions. A major hurdle was the distinction between "external" births such as chicken eggs and the delivery method of dogs, horses and humans. Ironically, it was challenges to Darwin's great insight that led to major advances in genetics. William Bateson sharply criticised Darwin's notion of "gradualism" in forming new species. Bateson thought that gradual change should be visible in animal populations and went looking for them. At the same time, another Darwin critic, Thomas Hunt Morgan, was examining thousands of fruit flies to learn how to identify what Bateson was seeking. Morgan was probably the most reluctant Darwinian since Charles Lyell, but was finally won over by his labouring students who demonstrated how genes worked. The buildup of the genome over the vast history of life on Earth becomes Gee's next topic. How did we get here and what's the present offer in the way of clues? He uses Graham Cairns Smith notion that the first step in creating a genome likely began in the dense environment of clay crystals. From this molecular origin, the author takes us to a menagerie of creatures, all of whom have something to contribute to the story. We are introduced to the mycoplasma - today's simplest creatures with less than 500 genes. Are they holdovers from an ancient form? We learn that parasites of bacteria have forced the trimming of genomes as a protective strategy. Why haven't we done the same, he asks, or are we in the process? The larger genome of humans, he reminds us, isn't sufficient to explain either our complexity or our uniqueness. Changes in our genome are traceable, with agriculture's introduction a major contributor. When the history of the study of the genome, whether fruit fly, bacterium or human, has been delineated, Gee takes the investigation a step further. He notes the propensity of the media to tout "a gene for" any number of traits, physical or behavioural. We must use the Internet as a model, he urges. The networking of many computers serves as a template for the information management of the genome. Genes, selfish as they may be in trying to reproduce, must cooperate in complex organisms. Single steps to gain single goals is no longer feasible, if it ever was. The intricate network of genome activity demands further attention. Like so many modern science writers, Gee chips away at Darwin iconology. He wants to demonstrate that all those "wrong" thinkers of the past made contributions. Unlike many iconoclasts, Gee keeps his critique muted, a welcome change. He also challenges us with questions about where the knowledge of the genome is leading. Knowledge of the human genome has the potential to elevate us from apes to angels. Are we prepared to face the issues that genome manipulation may generate? If you read this book, you will understand his concern. With the knowledge he provides, you will be more prepared.
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