Genetics

The cell is the basic building block of life. In its 3.5 billion years on the planet, it has proven to be a powerhouse, spreading life first throughout the seas, then across land, developing the rich and complex diversity of life that populates the planet today.               With The Cell: A Visual Tour of the Building Block of Life, Jack Challoner treats readers to a visually stunning tour of these remarkable molecular machines. Most of the living things we're familiar with--the plants in our gardens, the animals we eat--are composed of billions or trillions of cells. Most multicellular organisms consist of many different types of cells, each highly specialized to play a particular role--from building bones or producing the pigment in flower petals to fighting disease or sensing environmental cues. But the great majority of living things on our planet exist as single cell. These cellular singletons are every bit as successful and diverse as multicellular organisms, and our very existence relies on them. The book is an authoritative yet accessible account of what goes on inside every living cell--from building proteins and producing energy to making identical copies of themselves--and the importance of these chemical reactions both on the familiar everyday scale and on the global scale. Along the way, Challoner sheds light on many of the most intriguing questions guiding current scientific research: What special properties make stem cells so promising in the treatment of injury and disease? How and when did single-celled organisms first come together to form multicellular ones? And how might scientists soon be prepared to build on the basic principles of cell biology to build similar living cells from scratch.

Over a decade ago, as the Human Genome Project completed its mapping of the entire human genome, hopes ran high that we would rapidly be able to use our knowledge of human genes to tackle many inherited diseases, and understand what makes us unique among animals. But things didn't turn out that way. For a start, we turned out to have far fewer genes than originally thought - just over 20,000, the same sort of number as a fruit fly or worm. What's more, the proportion of DNA consisting of genes coding for proteins was a mere 2%. So, was the rest of the genome accumulated 'junk'? Things have changed since those early heady days of the Human Genome Project. But the emerging picture is if anything far more exciting. In this book, John Parrington explains the key features that are coming to light - some, such as the results of the international ENCODE programme, still much debated and controversial in their scope. He gives an outline of the deeper genome, involving layers of regulatory elements controlling and coordinating the switching on and off of genes; the impact of its 3D geometry; the discovery of a variety of new RNAs playing critical roles; the epigenetic changes influenced by the environment and life experiences that can make identical twins different and be passed on to the next generation; and the clues coming out of comparisons with the genomes of Neanderthals as well as that of chimps about the development of our species. We are learning more about ourselves, and about the genetic aspects of many diseases. But in its complexity, flexibility, and ability to respond to environmental cues, the human genome is proving to be far more subtle than we ever imagined.