Table Of ContentHarper’s Practical
Genetic Counselling
Eighth Edition
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Harper’s Practical
Genetic Counselling
Eighth Edition
Angus Clarke
Clinical Professor, Division of Cancer and Genetics
School of Medicine, University of Cardiff
Honorary Consultant, All Wales Medical Genetics Service, UK
with contributions from
Dr Alex Murray and Professor Julian Sampson
CRC Press
Taylor & Francis Group
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© 2020 by Taylor & Francis Group, LLC
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Library of Congress Cataloging-in-Publication Data
Names: Clarke, Angus, 1954-author. | Harper, Peter S. Practical genetic counselling.
Title: Harper’s practical genetic counselling / Angus Clarke.
Other titles: Practical genetic counselling
Description: Eighth edition | Boca Raton : CRC Press, [2020] | Preceded by Practical genetic counselling /
Peter S. Harper. 7th ed. 2010. | Includes bibliographical references and index. | Summary: ‘Easy to use, and
useful when kept close at hand in the room where you work. The book is a pleasure to read: the style elegant
and authoritative’ Lancet. ‘...this book is a wonderful reference to enable primary physicians to be informed
about their patients’ Annals of Internal Medicine. Universally used across the world by genetic counsellors,
medical geneticists and clinicians alike, Harper’s Practical Genetic Counselling has established itself as the
essential guide to counselling those at risk from inherited disorders. Increasingly, common disorders are
known to have a genetic component and this book provides invaluable and up to date guidance through the
profusion of new information in this area and the associated psychosocial and ethical considerations and
concerns. Within its established, tried and trusted framework, the book contains new chapters on: laboratory
methods, new genetic sequencing techniques and the applications of genome-wide SNP association studies,
genetic susceptibility, cross-cultural aspects and the genetic counselling process. It has expanded chapters
on genetic screening and screening of newborns, treatment techniques and rational approaches to treatment,
non-Mendelian inheritance, free fetal DNA in prenatal screening and diagnosis. Key features: - Fully updated
to provide the very latest information when in a busy consulting room or clinic - Clear and authoritative
advice applicable to everyday clinical practice - Reflects the rapid development of knowledge in this area,
including the implications of the human genome project and related technology. The eighth edition of this
popular, best-selling text continues to be an essential source of reference for trainee and practitioner genetic
counsellors, medical geneticists and clinicians. Also it provides valuable background for specialist nurses,
counsellors, social scientists, ethicists as well as genetics laboratory staff.-- Provided by the publisher.
Identifiers: LCCN 2019025219 | ISBN 9781444183740 (paperback ; alk. paper) | ISBN 9780367371906
(hardback ; alk. paper) | ISBN 9780367371944 (eBook)
Subjects: MESH: Genetic Counseling--methods | Genetic Techniques | Genetic Diseases, Inborn--genetics
Classification: LCC RB155.7 | NLM QZ 52 | DDC 362.196/042--dc23
LC record available at https://lccn.loc.gov/2019025219
Visit the Taylor & Francis Web site at
http://www.taylorandfrancis.com
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Contents
Preface to Eighth Edition vii
Acknowledgements ix
PArt 1 GENErAL ASPECtS OF GENEtICS AND GENEtIC COUNSELLING 1
1 Genetics and genetic counselling: An introduction 3
2 Genetic counselling in Mendelian disorders 23
3 Common disorders and genetic counselling 55
4 Chromosome abnormalities 67
5 Genetic and genomic investigations 89
6 Dysmorphology and genetic syndromes 111
7 Carrier testing 123
8 Predictive genetic testing 135
9 Prenatal diagnosis, antenatal screening and reproductive aspects of medical
genetics 145
10 Special issues in genetic counselling 171
11 Clinical genetics services 187
12 Treatments and trials for genetic disease 201
PArt 2 GENEtIC COUNSELLING: Specific organ systems 211
13 Neuromuscular disorders 213
14 Central nervous system: Paediatric and neurodevelopmental disorders 227
15 Central nervous system: Adult-onset and psychiatric disorders 253
16 Disorders of bone and connective tissue 273
17 Oral and craniofacial disorders 291
18 The skin 299
19 The eye 311
20 Deafness 323
21 Cardiac and cardiovascular disorders 329
22 Respiratory disorders 345
23 The gastrointestinal tract 349
24 Renal and urinary tract diseases 359
v
vi Contents
25 Endocrine and reproductive disorders 367
26 Inborn errors of metabolism 379
27 Disorders of blood and immune function 387
28 Environmental hazards 395
PArt 3 GENEtIC COUNSELLING AND tEStING FOr CANCEr 405
ALEX MURRAY AND JULIAN SAMPSON
29 Cancer as a genetic disorder 407
30 Colorectal cancer syndromes 411
31 Breast and ovarian cancer 415
32 Rare Mendelian cancer syndromes and other cancers 421
PArt 4 GENEtIC COUNSELLING IN CONtEXt: the broader picture 431
33 Communication in genetic counselling 433
34 Population aspects of genetic counselling and genetic screening 439
35 Genetics, society and the future 457
Glossary 469
Appendix 1: Further reading and Information 475
Appendix 2: Practical Genetic Counselling – the life story of a book 495
Index 501
Preface to Eighth Edition
This book, the creation of Peter Harper, has filled a valuable role over four decades in Britain
and around the world. I very much hope that this revised edition will continue this into the era
of genomic approaches to genetic diagnostics.
When revising Harper’s Practical Genetic Counselling, I had three target audiences in mind:
1. Healthcare practitioners, working across the full spread of medicine, who may wish to
appreciate what a referral to a medical genetics service entails and to understand the place
of genetic investigations when such a diagnosis is suspected. I hope this volume may support
the interested practitioner in that crucial first step of discussing cases and questions with the
clinical geneticists and genetic counsellors in their local genetics service. If so, this volume
will then have succeeded in promoting the appropriate mainstreaming of genetics into the
rest of medicine.
2 . Healthcare professionals training to work as specialists within a medical genetics service, as
clinical geneticists or genetic counsellors. This book aspires to provide an initial orientation
to the field and help students to gain familiarity both with the ‘medical facts’ of a condition
and, to some extent, with the emotions that arise in this context.
3. Medical and nursing practitioners who wish to understand enough about clinical aspects
of genetics to provide a basic level of genetic information and appropriate support to their
patients and their patients’ families. This is especially important for those working in settings
where a referral to a genetics specialist is not readily available.
Let us hope that this eighth edition of this book will enable it to meet the needs of these three
groups of practitioners and students as we approach the third decade of the third millennium!
Angus Clarke
vii
Acknowledgements
I would like to thank Peter Harper for giving me the opportunity to undertake this revision of
his book. However, I must also apologise to him for having taken so long to complete this task!
In addition, I must thank my colleagues Dr Alex Murray and Professor Julian Sampson for their
revision of the material on the genetics of cancer, which has grown from a single chapter, and
to Professor Gareth Evans (of Manchester University) for his most helpful advice on Table 31.1.
I am also most grateful to my colleague Dr Vinod Varghese for reading through and making
helpful comments on a draft of Chapter 9, for the comments of Sian Morgan on Chapter 4
and the comments of Dr Mark Rogers on the section on ‘Facioscapulohumeral Dystrophy’ in
Chapter 13.
I would also like to thank those who have assisted with diagrams and figures. This is especially:
Jan Sharp, Medical Illustrator in Cardiff, for the new diagrams; the Wales Genomics Laboratory
for permission to reproduce the array CGH results demonstrating a deletion of chromosome
15q provided by Sian Corrin; the team at DECIPHER (especially Dr Helen Firth and Julia
Foreman) for their permission to represent the DECIPHER browser both in a figure and on
the cover of the book; and Dr Andrew Fry for his assistance in making this interesting visually.
Of course, I am to blame for all errors that remain but I thank my colleagues heartily for their
support. I am also grateful to Jane, my wife, for her understanding and forbearance.
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