Table Of ContentElements of Medical Genetics
EMERY’S
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EMERY’S
Elements
of Medical
Genetics
14th EDITION
Peter D. Turnpenny
BSc, MB, ChB, FRCP, FRCPCH
Consultant Clinical Geneticist
Royal Devon and Exeter Hospital
and
Honorary Senior Clinical Lecturer
Peninsula Medical School
Exeter, United Kingdom
Sian Ellard
BSc, PhD, FRCPath
Consultant Clinical Molecular Geneticist
Royal Devon and Exeter Hospital
and
Professor of Human Molecular Genetics
Peninsula Medical School
Exeter, United Kingdom
1600 John F. Kennedy Blvd.
Ste 1800
Philadelphia, PA 19103-2899
EMERY’S ELEMENTS OF MEDICAL GENETICS ISBN: 978-0-7020-4043-6
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To our fathers—
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Preface
Since the publication of the thirteenth edition of Emery’s
Elements of Medical Genetics there has been a huge surge
forward in our knowledge and understanding of the human
genome as the technology of microarray comparative
genomic hybridization has been extensively applied, both in
research and clinical service settings. We know so much
more about the normal variability of the human genome as
the extent of copy number variants (of DNA) has become
clearer, though we are still trying to unravel the possible
significance of these in relation to health and disease. And
as we write this there is great excitement about the next
technological revolution that is underway, namely next
generation sequencing. Already there are dramatic examples
of gene discovery in mendelian conditions through analysis
of the whole exome of very small numbers of patients with
clear phenotypes. There is also more realistic anticipation
than before that breakthroughs will be made in the treat-
ment of genetic disease, which will take a variety of differ-
ent forms. Whilst discovery and knowledge proceed apace,
however, the foundation for those who aspire to be good
clinical practitioners in this field lies in a thorough grasp of
the basics of medical genetics, which must include the
Alan E.H. Emery ability to counsel patients and families with sensitivity and
Emeritus Professor of Human Genetics & Honorary Fellow explain difficult concepts in simple language.
University of Edinburgh In this fourteenth edition of Emery’s Elements of Medical
Genetics we have tried to simplify some of the language and
reduce redundant text where possible, to make way for
“A man ought to read just as inclination leads him; for what
some new, updated material. Several chapters have under-
he reads as a task will do him little good.”
gone significant revisions, and the range of illustrations has
Dr. Samuel Johnson
increased. We have listened to those colleagues (a small
Advances and breakthroughs in genetic science are continu- number!) who identified one or two errors in the last edition
ally in the news, attracting great interest because of the and also suggested ideas for improvement. Once again, we
potential, not only for diagnosing and eventually treating have sought to provide a balance between a basic, compre-
disease, but also for what we learn about humankind through hensive text and one that is as up to date as possible, still
these advances. In addition, almost every new breakthrough aiming at medical undergraduates and those across both
raises a fresh ethical, social, and moral debate about the uses medical and non-medical disciplines who simply want to
to which genetic science will be put, particularly in repro- “taste and see.” The basic layout of the book has not changed
ductive medicine and issues relating to identity and privacy. because it seems to work well, and for that we remain in
Increasingly, today’s medical graduates, and mature post- debt to our predecessors in this project, namely Alan Emery,
graduates, must be equipped to integrate genetic knowledge Bob Mueller, and Ian Young.
and science appropriately into all areas of medicine, for the
task cannot be left solely to clinical geneticists, who remain Peter D. Turnpenny and Sian Ellard
small in number; indeed, in many countries there is either Exeter, United Kingdom
no structured training program in clinical genetics or the November 2010
specialty is not recognized at all.
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Acknowledgments
As with the previous two editions, we are very grateful Dr. Rachel Freathy (Sir Henry Wellcome Postdoctoral
to those of our patients who were asked for consent to Fellow, Peninsula Medical School, Exeter) provided new
publish their photographs for the first time; again, not one insights and assisted with revision of the chapters describing
refused, which was enormously helpful. In preparation of polygenic inheritance and common disorders. We thank
this edition we thank colleagues who cast a critical but those at Elsevier who communicated very fully and promptly
very constructive eye over particular chapters, which led throughout the revision, and were patient with delays on
to some very necessary changes to the text. These were our part. We again thank those at our respective homes who
Dr. Paul Kerr (Consultant Hematologist, Royal Devon had to put up with a season of early mornings and late
and Exeter Hospital, Exeter) and Dr. Claire Bethune nights, without which the revision would not have been
(Consultant Immunologist, Derriford Hospital, Plymouth). possible.
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