Page 10 - Genetics_From_Genes_to_Genomes_6th_FULL_Part1

Preface

A Note from the Authors ∙ Human genetics: how genes contribute to health and
diseases, including cancer.
The science of genetics is less than 150 years old, but its ∙ The unity of life-forms: the synthesis of information
accomplishments within that short time have been aston- from many different organisms into coherent models.
ishing. Gregor Mendel first described genes as abstract ∙ Molecular evolution: the molecular mechanisms by
units of inheritance in 1865; his work was ignored and which biological systems, whole organisms, and
then rediscovered in 1900. Thomas Hunt Morgan and his populations have evolved and diverged.
students provided experimental verification of the idea
that genes reside within chromosomes during the years The strength of this integrated approach is that students
1910–1920. By 1944, Oswald Avery and his coworkers who complete the book will have a strong command of
had established that genes are made of DNA. James genetics as it is practiced today by both academic and cor-
Watson and Francis Crick published their pathbreaking porate researchers. These scientists are rapidly changing
structure of DNA in 1953. Remarkably, less than 50 years our understanding of living organisms, including ourselves.
later (in 2001), an international consortium of investiga- Ultimately, this vital research may create the ability to re-
tors deciphered the sequence of the 3 billion nucleotides in place or correct detrimental genes—those “inborn errors of
the human genome. Twentieth century genetics made it metabolism,” as researcher Archibald Garrod called them
possible to identify individual genes and to understand a in 1923, as well as the later genetic alterations that lead to
great deal about their functions. the many forms of cancer.
Today, scientists are able to access the enormous
amounts of genetic data generated by the sequencing of
many organisms’ genomes. Analysis of these data will re- The Genetic Way of Thinking
sult in a deeper understanding of the complex molecular Modern genetics is a molecular-level science, but an under-
interactions within and among vast networks of genes, pro- standing of its origins and the discovery of its principles is
teins, and other molecules that help bring organisms to life. a necessary context. To encourage a genetic way of think-
Finding new methods and tools for analyzing these data will ing, we begin the book by reviewing Mendel’s principles
be a significant part of genetics in the twenty-first century. and the chromosomal basis of inheritance. From the outset,
Our sixth edition of Genetics: From Genes to Genomes however, we aim to integrate organism-level genetics with
emphasizes both the core concepts of genetics and the fundamental molecular mechanisms.
cutting-edge discoveries, modern tools, and analytic meth- Chapter 1 presents the foundation of this integra-
ods that will keep the science of genetics moving forward. tion by summarizing the main biological themes we
The authors of the sixth edition have worked together explore. In Chapter 2, we tie Mendel’s studies of pea
in revising every chapter in an effort not only to provide the trait inheritance to the actions of enzymes that deter-
most up-to-date information, but also to provide continuity mine whether a pea is round or wrinkled, yellow or
and the clearest possible explanations of difficult concepts green, etc. In the same chapter, we point to the related-
in one voice. ness of the patterns of heredity in all organisms.
Chapters 3–5 cover extensions to Mendel, the chromo-
Our Focus—An Integrated Approach some theory of inheritance, and the fundamentals of
gene linkage and mapping. Starting in Chapter 6, we
Genetics: From Genes to Genomes represents a new approach focus on the physical characteristics of DNA, on muta-
to an undergraduate course in genetics. It reflects the way tions, and on how DNA encodes, copies, and transmits
we, the authors, currently view the molecular basis of life. biological information.
We integrate:
Beginning in Chapter 9, we move into the digital revo-
∙ Formal genetics: the rules by which genes are lution in DNA analysis with a look at modern genetics
transmitted. techniques, including gene cloning, PCR, microarrays, and
∙ Molecular genetics: the structure of DNA and how it high-throughput genome sequencing. We explore how
directs the structure of proteins. bioinformatics, an emergent analytical tool, can aid in dis-
∙ Digital analysis and genomics: recent technologies covery of genome features. This section concludes in
that allow a comprehensive analysis of the entire gene Chapter 11 with case studies leading to the discovery of
set and its expression in an organism. human disease genes.

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