Review: Genes & DNA by Richard Walker

Ever since I was little, I have been a huge fan of reference books like these, published by Kingfisher Books or Dorling Kindersley. This one, Genes & DNA by Richard Walker (foreword by Steve Jones) is published by Kingfisher.

Genes & DNA is perfect for children from 10 to 16. It covers a lot of interesting topics, including what genes are, how they are passed from one generation to another, the nature of nurture debate, twins, DNA, the Human Genome Project, evolution, DNA fingerprinting, mutations, genetic engineering, screening for diseases, gene therapy and possible future technologies, complete with glossary, index and further reading!

The author, Richard Walker, is an award-winning science writer and is the author of a wide range of books on the human body, biology and natural history. He has a BSc and PhD in zoology, and he spent several years teaching biology in London schools before becoming a full-time writer. (Source: PanMacmillan)

The writing is very clear and concise so explanations for something as complicated as DNA replication are easy to understand. I think it's a perfect introduction to genetics as it covers such a wide range of topics. And the fantastic illustrations and photographs make this book all the more interesting and entertaining to read.

It is great that this book also cover some history, talking about Gregor Mendel's pea experiments. He looked at how breeding pure-breed purple-flowered plants with pure-breed white-flowered plants results in purple-flowered first generation plants, but in the second generation, 25% of plants are white-flowered. This is down to the dominance of genes. His experiments show that the alleles, or the genes, for the white flowers are recessive (and so can only come from two parents that are carriers of the allele).

The experiments described in the book are only to do with the colours of the flowers of the plants, but I believe there were other further experiments regarding the height of the plants (pea plants can only either be tall or short, suggesting this to be a monogenic characteristic - a trait controlled by one gene only), the position of the flowers on the plant, the seed and pod colour and the seed and pod shape.

My favourite section is the chapter on the nature or nurture debate. The book explores this very well, explaining that our genes "provide the plan for our bodies" but that "this plan can be moulded by our surroundings." The chapter also leads on very well to the chapter on twins, explaining that perfect pitch is shown to be largely genetic because usually both of the genetically identical twins have perfect pitch, or no perfect pitch - not one of the twins having perfect pitch and the other, without this ability.

Other questions are answered like, "Are sumo wrestlers naturally fat, or do they do something to make them fat?" The answer is that the surroundings (the diet) affect sumo wrestlers more than the genes do, so sumo wrestlers will not necessarily have overweight children. Another question is posed, "Can your blood type be changed?", the answer to which is that it cannot be changed because your DNA determines your blood type (which is determined by the antigens, or proteins on the surface of red blood cells).

As an aside, there are some factors that can change your blood type, like an infection or an autoimmune disease, which causes the addition or suppression of an antigen. These are, however, not covered by the book, but I don't think this is necessary for a book for children, as the changing of blood type is VERY rare!

I highly recommend Genes & DNA to anyone interested in this fascinating science! There is so much more to this science than most people realise and this book truly broadens horizons.

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