Mobilizing Mutations: Human Genetics in the Age of Patient Advocacy

By Daniel Navon

With every passing year, more and more people learn that they or their young or unborn child carries a genetic mutation. But what does this mean for the way we understand a person? Today, genetic mutations are being used to diagnose novel conditions like the XYY, Fragile X, NGLY1 mutation, and 22q11.2 Deletion syndromes, carving out rich new categories of human disease and difference. Daniel Navon calls this form of categorization “genomic designation,” and in Mobilizing Mutations he shows how mutations, and the social factors that surround them, are reshaping human classification.
 
Drawing on a wealth of fieldwork and historical material, Navon presents a sociological account of the ways genetic mutations have been mobilized and transformed in the sixty years since it became possible to see abnormal human genomes, providing a new vista onto the myriad ways contemporary genetic testing can transform people’s lives.
 
Taking us inside these shifting worlds of research and advocacy over the last half century, Navon reveals the ways in which knowledge about genetic mutations can redefine what it means to be ill, different, and ultimately, human.
 

• Language: English
• Publisher: University of Chicago Press
• Release date: Sep 20, 2019
• ISBN: 9780226638126

Book preview

Mobilizing Mutations

Mobilizing Mutations

Human Genetics in the Age of Patient Advocacy

Daniel Navon

The University of Chicago Press    Chicago and London

The University of Chicago Press, Chicago 60637

The University of Chicago Press, Ltd., London

© 2019 by The University of Chicago

All rights reserved. No part of this book may be used or reproduced in any manner whatsoever without written permission, except in the case of brief quotations in critical articles and reviews. For more information, contact the University of Chicago Press, 1427 E. 60th St., Chicago, IL 60637.

Published 2019

Printed in the United States of America

28 27 26 25 24 23 22 21 20 19    1 2 3 4 5

ISBN-13: 978-0-226-63809-6 (cloth)

ISBN-13: 978-0-226-63812-6 (e-book)

DOI: https://doi.org/10.7208/chicago/9780226638126.001.0001

Library of Congress Cataloging-in-Publication Data

Names: Navon, Daniel, author.

Title: Mobilizing mutations : human genetics in the age of patient advocacy / Daniel Navon.

Description: Chicago : The University of Chicago Press, 2019. | Includes bibliographical references and index.

Identifiers: LCCN 2019009779 | ISBN 9780226638096 (cloth : alk. paper) | ISBN 9780226638126 (e-book)

Subjects: LCSH: Human chromosome abnormalities. | Medical genetics. | Human genetics. | Mutation (Biology)

Classification: LCC RB155.5 .N38 2019 | DDC 616/.042—dc23

LC record available at https://lccn.loc.gov/2019009779

This paper meets the requirements of ANSI/NISO Z39.48-1992 (Permanence of Paper).

for Claire Bear

Contents

Acknowledgments

Introduction: From Mutations to New Kinds of People

1   Genomic Designation: How Genetics Creates New Medical Conditions

2   Immobile Mutations: Nowhere to Go in the 1960s and 1970s (and the Exception That Proves the Rule)

3   Leveraging Mutations: Going from the Rare to the Common in Human Genetics

4   The Loops That Tie: Mutations in the Trading Zone of Autism Genetics

5   Assembling a New Kind of Person

6   Mutations in the Clinic: Reframing Illness and Redirecting Medical Practice

7   Remaking the Normal versus the Pathological in Genetic Medicine

8   The Future for Genomic Designation and the New Prenatal Testing Landscape

Conclusion

Notes

References

Index

Acknowledgments

The first note of thanks goes to the many researchers, clinicians, caregivers, and patient advocates who took the time to share their perspectives and their stories with me. Above all, I am enormously grateful for the opportunity to meet so many people and families dealing with the genetic conditions discussed in this book. Although I was not able to formally interview patients themselves, spending time with them and their families enriched my thinking and my understanding immeasurably. I hope that this book helps open the door for research that directly addresses their perspectives and starts to unpack important policy questions about the way our knowledge about genetic mutations is shaping their lives.

I am grateful for research support from the Robert Wood Johnson Foundation, the UC San Diego Hellman Fellows Program, and the Binational Science Foundation. In addition, Columbia’s Mellon Foundation Fellows Program and Lindt and Lazarsfeld Fellowships, as well as its Institute for Social and Economic Research and Policy and Department of Sociology, provided crucial support at an earlier stage of this project.

Various parts of this book were presented at dozens of conferences, workshops, and talks over the years—thank you to everyone who posed challenging questions or provided helpful feedback. Parts of chapter 1 were published in much earlier form as follows: Daniel Navon, Genomic Designation: How Genetics Can Delineate New, Phenotypically Diffuse Medical Categories, Social Studies of Science 41, no. 2 (2011): 203–26; and Daniel Navon and Uri Shwed, The Chromosome 22q11.2 Deletion: From the Unification of Biomedical Fields to a New Kind of Genetic Condition, Social Science & Medicine 75, no. 9 (2012): 1633–41. Most of chapter 4 is composed of revised versions of Daniel Navon and Gil Eyal, The Trading Zone of Autism Genetics: Examining the Intersection of Genomic and Psychiatric Classification, BioSocieties 9, no. 3 (2014): 329–52; and Daniel Navon and Gil Eyal, Looping Genomes: Diagnostic Change and the Genetic Makeup of the Autism Population, American Journal of Sociology 121, no. 5 (2016): 1416–71. My thanks go to the anonymous reviewers and journal editors who helped further my thinking.

My editor, Karen Merikangas Darling, deftly guided this book through to publication, and the anonymous reviewers for the University of Chicago Press provided a series of extremely helpful suggestions that made for a much stronger manuscript. Nicholas Murray’s meticulous copyediting, along with the contributions of the rest of the production team, helped to bring the book past the finish line and into print.

A number of scholars at Columbia and elsewhere read my early work on this topic and provided sage advice about the best ways forward. I am especially grateful to Sarah Franklin, Herbert Gans, Dani Lainer-Vos, Uri Shwed, Shamus Khan, Eviatar Zerubavel, Bill McAllister, Martine Lappé, Amy Hinterberger, Brendan Hart, Des Fitzgerald, Nikolas Rose, Charles Tilly, Diane Vaughan, and Nadia Abu El-Haj.

More recently, I was very fortunate to receive incisive feedback from Hannah Landecker, Aaron Panofsky, James Evans, Adrian Johns, Peter Marsden, Jason Beckfield, Kathy Swartz, Ilana Löwy, Mattias Smångs, Eric Engles, Fernando Domínguez Rubio, Kwai Ng, Jeff Haydu, and John Evans. A special note of thanks goes to Stefan Timmermans, Sara Shostak, and Alberto Cambrosio for their incredibly generous feedback and advice over the past few years.

Peter Bearman helped a recovering philosophy student learn how to think like a sociologist, albeit an unusual one. He also made a spirited case for writing this book. For that and much more I am very grateful.

I owe an extraordinary debt of gratitude to my advisor, Gil Eyal. From the very beginning of this project, Gil was unwaveringly generous with his time, his feedback, and his advice on matters big and small. This book would be far poorer were it not for his brilliant input, guidance, and encouragement. Suffice it to say I can only hope to one day be such a mentor.

Endless thanks go to the many friends and colleagues who have provided support and advice over the years. You are too many to name, but you have enriched my work and my life in countless ways. I cannot resist singling out a few especially supportive colleagues and cherished friends: Amy Binder, Kevin Lewis, Juan Pablo Pardo-Guerra, Akos Rona-Tas, John Evans, Abigail Andrews, Saiba Varma, Aftab Jassal, Cathy Gere, Laleh Khalili, John Chalcraft, Roz Redd, Jeffrey Lenowitz, Dan Meller, Matt Spooner, Isabel Harland de Benito, Phil Bachelor, Eilidh McPherson, Tom Scott-Smith, James Golden, Cynthia Littlestone, Zac McGowan, and John Keefe.

To my family—especially Larry, Simone, Joshua, and Jimby Navon; Pam, Bill, and Billie Edington; Lisa Clarke; Zev Weiser; and Henry and Renee Bernstein—thank you for your understanding and encouragement throughout this process. Special thanks go my parents, Larry and Simone, and my grandfather, Howard Weiser, for instilling an enduring curiosity about the world and the drive to pursue it.

Finally, I can barely even begin to express what my partner and wife, Claire Edington, has meant to me throughout this process. Claire read drafts of almost every chapter and helped to make each one more elegant and more cogent. She helped me overcome obstacles and frustrations big and small, and together we have safely navigated the early stages of this strange career. Most of all, from the time we met just over a decade ago, Claire has made me a better and far happier person. I can hardly imagine a life without her and our amazing baby girl, Lyla Navon.

Introduction: From Mutations to New Kinds of People

The rapid expansion of DNA testing continues apace. With every passing year, more and more people learn that they, their child, or their fetus carry a genetic mutation. But what does finding a mutation actually mean for the way we understand a person? What does it tell us about her fate? Despite all the ink that has already been spilt answering that question, this book shows how having a genetic mutation can mean even more than we realized.

Take the example of someone who is missing a segment of DNA at site 11.2 (pronounced one-one-point-two) on the long arm of one of their twenty-second chromosomes. The 22q11.2 microdeletion is often detected via a fluorescence in situ hybridization, or FISH, test that binds bright probes to a particular location on a chromosome. The absence of a probe indicates a missing segment of a chromosome that would otherwise be too small to see under a microscope. If one of the 22q11.2 probes is missing, as seen in figure 1, then the person in question probably has a 22q11.2 microdeletion—a mutation that likely affects nearly every cell of her body.

Today, finding this mutation means that a person has 22q11.2 Deletion Syndrome, one of the most common genetic disorders after Down syndrome (Bassett et al. 2011; Grati et al. 2015). It means that she and her family have access to a growing network of care, support, advocacy, and biomedical research headlined by the International 22q11.2 Foundation. Despite its genomic specificity, 22q11.2 Deletion Syndrome (DS) affects people in dramatically different ways. They can have medical issues ranging from schizophrenia and autism to constipation, malar flatness, and hypocalcemia. Congenital heart defects and developmental delays may also result from 22q11.2DS, or it may produce such a mild phenotype that no one will ever even think to refer the patient for genetic testing (McDonald-McGinn et al. 2001). Finally, finding the microdeletion at 22q11.2 is increasingly likely to mean that parents face a dilemma about whether to terminate a pregnancy (Bretelle et al. 2010; chapter 8 below). Numbers are rising fast, mostly in North America and Europe, but also in India, Thailand, Chile, and elsewhere, and 22q11.2DS is the focus of a growing network of specialist clinics, support groups, pharmaceutical trials, and advocacy organizations.

Figure 1. A fluorescence in situ hybridization (FISH) test indicating a microdeletion at 22q11.2. The absence of a Tuple 1 probe on one of the copies of chromosome 22, along with the presence of the ARSA control probe, indicates a missing segment of DNA at site q11.2 (Tonelli et al. 2007). (Image reproduced under the Creative Commons Attribution License; http://creativecommons.org/licenses/by/2.0)

I want to explain how the absence of a bright dot on an image of stained chromosomes—or any other test indicating a genetic mutation—can distinguish between two clinically indistinguishable patients and provide entrée to a burgeoning network of research, care and activism. This is not social science fiction, but a way of classifying people with a sixty-year history. By studying that history, I argue, we can better grasp how, when and why genetics can radically reshape the way we understand and act on human difference.

Ever since human geneticists started discovering people with abnormal genomes, they have used two different strategies to make sense of the relationship between mutations and disease. The first strategy is easy to grasp. In March 1959, a team of human geneticists in Paris reported that all nine of their patients with Mongolian Idiocy had three copies of chromosome 21 rather than the normal two (Lejeune, Gautier, and Turpin 1959). They had discovered a fairly clear-cut chromosomal explanation of an established medical condition—the first gene for an important category of human difference. The association between Mongolian Idiocy, now known as Down syndrome, and trisomy 21 was a true game-changer. It catapulted the field of cytogenetics—the study of chromosomes—into medical salience and helped lay the foundation for the rise of medical genetics (Harper 2006; Neri and Opitz 2009). Decades later, the idea that genetic mutations might explain many important medical conditions helped animate the Human Genome Project, not to mention our broader turn-of-the-century fascination with the book of life. These grand hopes for medical genetics were significantly bolstered by a handful of findings in the late 1980s and early 1990s, not least the discoveries of the genes that cause Tay-Sachs disease, cystic fibrosis, and Huntington’s disease.

Yet if we have learned anything about human genetics since the optimistic 1990s, it is that surprisingly few important questions of health and illness find straightforward answers in our DNA (Check Hayden 2008; Kolata 2012b; Lock 2005; Wade 2009). For the most part, the relationship between our genomes and the traits or diseases that shape our lives is just far more complex and uncertain than almost anyone anticipated. Simply put, there is no gene for the vast majority of common medical conditions. The front line of clinical genomics for the general population is instead about reporting variants in several dozen genes that mostly confer risk for cancers and heart issues, such as cardiomyopathies or Long QT syndrome (Trivedi 2017). Nevertheless, the 1959 discovery of trisomy 21 continues to shape our thinking about what genetics can and should do for our understanding of disease and difference.

The second strategy for making sense of genetic mutations came into view just months after the first. In September 1959, a team of researchers in Scotland found a super female with three X chromosomes instead of the normal female complement of two (Jacobs, Baikie, et al. 1959). Then, in April 1960, the Lancet published back-to-back reports of two new chromosomal abnormalities: a team based in Wisconsin reported a patient with trisomy 13, while another group in England reported one with trisomy 18 (Edwards et al. 1960; Patau et al. 1960). It turned out that most of the approximately one in one thousand women who have trisomy X are so mildly affected that they never come to the attention of a medical geneticist. By contrast, trisomy 13 and 18 tend to cause severe malformations that usually lead to prenatal or early childhood death. However, all three chromosome abnormalities had one thing in common: unlike trisomy 21, none of them lined up with an established disorder. The XXX abnormality was clearly not a gene for an already-recognized disorder. Triple X syndrome, as it came to be known, was a new condition that could never have been discovered or diagnosed until we were able to find and identify people with three X chromosomes. Genetics had shown that it could do more than help us explain, predict, or treat the medical conditions we already know and care about. Almost as soon as we began to find people with abnormal genomes, a wave of new genetic disorders started coming into view.

In this book, I show how knowledge about genetic mutations is being used to carve out new and otherwise unthinkable medical conditions that are shaping people’s lives in ever more powerful ways. I call this way of classifying people genomic designation. The stakes are high. 22q11.2DS and Triple X syndrome are just two among a rapidly growing number of conditions that are delineated strictly according to genetic mutations. Many have become powerful categories of human difference in recent years, even though they lack the distinctive phenotype of a condition like Down syndrome. Although statistics are not available, there is no question that many thousands of people have been diagnosed with genomically designated conditions and that many millions are so diagnosable. This turn to genomic classification has gained considerable steam in just the last few years, and there is good reason to believe that it will come to occupy a far greater role in the way we understand people who are disabled or developmentally different in the coming decades. Most of these mutations are rare, but cumulatively they are not rare at all. With recent advances in genetic testing (both pre- and postnatal), the number of people actually being diagnosed with genomically designated conditions is skyrocketing. Meanwhile, new mutations are joining the fray all the time. We also need to keep in mind how quickly things are moving. It is becoming ever easier to identify mutations and then use databases and communications technologies to create cohorts of patients, even if they are, quite literally, very few and far between.

This new way of classifying human difference has now gained traction far afield from the pages of genetics journals. From 5p− and XYY syndrome to Fragile X and NGLY1 deficiency, growing networks of research, clinical practice and advocacy are being organized around specific genetic mutations. Throughout this book, I trace the way some of these genomically designated conditions have given rise to innovative patient advocacy movements, new hybrid communities, perplexing biosocial identities, exacting clinical guidelines, and newfangled approaches to human difference. In some cases, knowing that a person has a genetic mutation can destabilize the thresholds of clinical significance—the very boundary between the normal and the pathological—for issues like IQ and childhood growth.

The significance of these mostly rare genetic disorders goes far beyond the people and families directly affected by the discovery of this or that mutation. We will see how a growing number of researchers and pharmaceutical companies are turning their attention to genomically designated conditions in the hope that they can leverage them as genetic models and thereby unlock the biological basis of common conditions like autism, schizophrenia, and heart disease, or even our human capacities for things like language or aggression. In this way, research on people with the mutations discussed in this book is often undertaken in pursuit of dual goals: understanding and helping people with a rare genetic disorder while simultaneously trying to get at less biologically tractable but much broader questions about human health, illness, and difference. In a way, my goals are not all that different. I argue that the mutations discussed throughout this book are important not only because they shape so many people’s lives, but also because their histories as objects of knowledge and practice help us get at a series of key issues in the social studies of science and medicine.

Genetics, Medical Classification, and Social Mobilization

Throughout this book, I show how genetic mutations can give rise to what philosopher Ian Hacking would call new kinds of people: the sort of classifications that really change the people they are applied to, even as the categories themselves are constantly changing as well. We will see how some mutations have become powerful objects of bioscientific research, clinical practice, social mobilization, and identity formation, even though experts could never pick their bearers out of a crowd based on what they are actually like—that is, their phenotype. But more than that, this book explains how genetic mutations can come to mean so much. I trace the way a mutation can begin its social career as a thin case report about a child with developmental delay and a handful of congenital abnormalities, but then metamorphose into a bona fide medical condition and eventually a richly detailed kind of person with a whole community built up around it. But how did this come to pass? What lessons does this new way of classifying disease hold for the way we understand the impact of genetics research on medicine and society?

Genomic designation opens the door for the social studies of science and medicine to follow the field of medical genetics away from a century-plus old Mendelian paradigm to a truly genomic one. We have begun to think seriously about genetic complexity in the sense of many genomic variants combining with a host of other factors to produce traits and disease outcomes. But that is just one side of the coin. We have barely scratched the surface of the way researchers are uncovering incredible complexity and far-reaching insights in single pathogenic mutations. Most genetic mutations—whether whole chromosome duplications or tiny DNA variants—do not line up with existing categories of human difference. From a Mendelian or gene-for perspective, this represents a gnarl of genetic complexity. From a genomic perspective, by contrast, it is nothing more than variable expressivity. The real disease is designated by the mutation—if it turns out to be less clear-cut than we thought, then so be it. This approach comes naturally enough to geneticists, but many physicians and even patient advocates have now embraced genomic designation as well.

Even when a newly discovered mutation seems to straightforwardly explain an older medical condition, further research almost inevitably produces important discrepancies between the people who have the mutation and the condition’s clinical diagnostic criteria. This can lead to a different variety of genomic designation where long-standing disorders are recalibrated and reclassified according to genetic mutations. Sometimes, experts and advocates embrace this sort of genomic designation even at the expense of patients who had received an older clinical diagnosis like Williams syndrome or DiGeorge syndrome, but do not have the mutation in question. In this way, genomic designation can turn patients who do not have a particular mutation into nosological orphans.

This turn to the genome as a locus of classification is perhaps best understood according to a series of ideal types. Genetic mutations are variously used to delineate entirely new medical conditions or to split, lump, and recalibrate more long-standing clinical categories. Genetic reductionism, or geneticization—that old friend of the human sciences—is only very rarely the best way to understand the relationship between mutations and kinds of people, and it is never perfectly realized. We need a new toolkit if we want to effectively grapple with twenty-first-century genomic medicine.

At the same time, we will see very clearly that genetics research on its own can only go so far. Just because a researcher talks about a new syndrome in the pages of a prestigious biomedical journal does not mean that it will ever inform clinical practice, never mind collective action and identity formation. A newly discovered mutation can indeed be seamlessly cast as a new disorder or syndrome in the esoteric field of human genetics research. And yet it still takes very particular historical conditions and years of painstaking work in order to make a mutation truly matter to a general practitioner, a behavioral psychologist, an educator, a biotech company, a concerned parent, or the people who are diagnosed with a funny-sounding genetic disorder. Whether or not a genetic mutation becomes salient in clinical practice or patient communities is never a given. It takes social mobilization to turn a mutation into a powerful category of identity and community formation—that much is obvious. But it also takes alliances of experts and activists to build up an understanding of the very phenotype of the mutation, develop effective treatment strategies, establish specialist clinics, and garner the resources necessary for a full-fledged research program.

In other words, what it means to have a genetic mutation is as much a sociological phenomenon as it is a biomedical one. What do I mean by that? We sociologists are increasingly refusing to confine ourselves to things we usually think of as social.¹ My aim here is to examine the admixture of processes and associations (Latour 2007:5–9) spanning a dizzying array of fields, objects, and actors that determine what it means to have a mutation. I do not try to explain away changes in what it means to have a mutation by making recourse to hidden social forces exerting an independent power over science and medicine. While I occasionally discuss the role of social processes in a mutation’s career, or even the relationship between genetics and society, these sorts of terms should be treated as convenient demarcations within a messier reality. A sociological approach will therefore help us understand what it means to have a mutation today, not because social factors exert some sort of dark power over biology, but because sociology can help us trace a host of key relations that biomedicine itself cannot. The mutations I discuss throughout this book make it abundantly clear that the distinction between biology and society is not a thing out there to be discovered, but a constantly shifting outcome of action and negotiation.

So Much Genomic Data, but What Is to Be Done with It?

We are in the midst of an enormous proliferation of data about our genomes. In 2001, it cost somewhere between $500 million and $1 billion to generate the first reference sequence of the roughly three billion bases in a human genome (National Human Genome Research Institute 2016); in late 2007, a somewhat lower-quality sequence of all three billion base pairs was $10 million; today it can be done for less than a thousand dollars, with a hundred-dollar genome promised in the very near future (Illumina 2017). That thousand-dollar figure has long been considered the threshold at which whole genome scans for mass consumption would begin to enter the market (Mardis 2006; Service 2006). With clear, quantitative improvements in existing technologies driving further reductions in cost, there is every reason to expect the price to continue its precipitous decline. We may well be on the cusp of the long-anticipated juncture where millions of people own annotations of their three billion DNA base pairs sequence. In any case, clinicians can already order a host of genomic assays capable of detecting thousands of mutations and variants for a fraction of what a test for a limited panel of genes cost just a few years ago. All this takes place against a backdrop where genetics has captured the public imagination and become a powerful component of both disease advocacy and perceptions of health and illness more generally (e.g., Condit 2010; Hacking 2006a; Nelkin and Lindee 2004).

Meanwhile, researchers are finding a far greater range and incidence of potentially pathogenic abnormalities than anticipated, even in seemingly normal people. Our current mutational repertoire includes tens of thousands of structural variants like copy number variants, or CNVs (see Lappé and Landecker 2015), and chromosomal abnormalities, as well as millions of smaller mutations. We all harbor numerous variations in our genomes that can shape what we are like. An average person may bear something like ten thousand DNA variants that affect protein production, several hundred more functionally powerful variants, such as indels and deletions, and fifty to one hundred variants in genes associated with inherited disorders (The 1000 Genomes Project Consortium 2010:1066). The average human genome also contains several rare copy number variants, with 5–10% carrying CNVs where more than five hundred thousand base pairs are either missing or duplicated, and 1–2% carrying CNVs of more than a million base pairs (Harel and Lupski 2018; Sebat et al. 2004). There is clearly no shortage of genetic difference out there.

At the same time, having that complete annotation of your genome is unlikely to tell you anything especially meaningful about your health. Most common medical conditions are genetically complex: researchers may find plenty of genes that are associated with this or that ailment, but each variant will only account for a tiny fraction of a common disease’s incidence. Most of them cause the disease in question only some of the time, and most are associated with other diseases and traits as well. To top it all off, even putting all these sorts of genomic variants together tends to leave the large bulk of the common disease’s incidence unexplained. Genetics is still a long way from providing convincing answers to questions about most common forms of disease and illness.

Nevertheless, genomic tests are being incorporated into clinical practice, despite the often ambiguous medical implications of the results they produce (Kohane, Masys, and Altman 2006; Manolio et al. 2013). Many mutations, it turns out, have expansive and multivalent spectrums of expression. Some can range from no symptoms at all to benign tumors and certain forms of cancer, heart malformations, autism, and developmental delay (e.g., Varga et al. 2009). Although attempts to standardize the interpretation of these kinds of tests have been published by the relevant professional organizations (ACMG Board of Directors 2012; Green et al. 2013; South et al. 2013), they remain limited to a prescribed list of well-characterized conditions. Beyond that, it takes considerable case-by-case deliberation among expert practitioners to decide which mutations to actually report to physicians, patients, and their families (Timmermans 2014). Even genetic markers that were thought to invariably cause specific disorders like phenylketonuria and cystic fibrosis are often found in people who do not have the expected clinical phenotype once screening is implemented, forcing researchers and clinicians to rethink established disease categories (Timmermans and Buchbinder 2013; Vailly 2008). And yet, genomic diagnoses are increasingly used to guide prognosis and care as part of a broader turn toward personalized medicine, especially when it comes to children with developmental disabilities and unexplained congenital malformations (Miller et al. 2010).

On the one hand then, we now look back at the euphoria animating late twentieth-century endeavors to pry open the book of life as an episode of remarkable hubris. For any given person, DNA is not likely to yield clear predictors for her future health (Kolata 2012a; Roberts et al. 2012). Simply put, long-standing questions about disease and difference rarely find clear answers in the Cs, Gs, As, and Ts that make up our genomes. On the other hand, staggering volumes of resources and an abundance of hope continue to be invested in genomics. The Human Genome Project has given way to its natural successor: the turn to using knowledge about people’s particular genomes, alongside the many factors that shape gene expression, to get at a range of questions about human health, illness, difference, and identity. This broader, postgenomic enterprise absorbs billions of dollars in funds across a panoply of fields. Genomics is therefore poised to exert a growing influence on people’s lives in the coming years, even though the project of making sense of all this DNA data is still in its infancy. So, with genetic testing becoming ever more rapid, precise, and affordable, what is to be done with all this knowledge about our surprisingly anomaly-ridden genomes?

Going Beyond Geneticization

The social sciences are currently at something of a loss when it comes to this important question. This is not because anyone doubts that genomics will continue to have profound social reverberations, nor is there any shortage of work on genetics and society. In fact, a significant interdisciplinary subfield has addressed not only the manifold implications of genetic testing, but also the way that social processes shape the production, diffusion, and use of knowledge about the human genome (for reviews, see Freese and Shostak 2009; Fujimura, Duster, and Rajagopalan 2008).

The problem, rather, is a seductive conceptual error that has guided the field since its earliest stirrings. The social studies of science and medicine have assumed that genetics must work in and through existing categories of human difference in order to really matter. For a time, this made sense. The gene-for model of associating genetic variants with established diseases and traits was much-hyped in 1991, when Abby Lippman coined the term geneticization: the idea that many categories of human difference would be reduced to their DNA codes, with most disorders, behaviors and physiological variations defined, at least in part, as genetic in origin (Lippman 1991a:19; see also 1991b, 1998). The prospect of widespread genetic reductionism raised important questions about medical practice, stigma, the experience of illness, and our capacity to situate health outcomes in social environments.

When it comes to actual genetics research, however, it turns out that human differences can only very rarely be reduced to changes in our DNA. With a handful of notable exceptions, the characteristics of our genomes do not line up neatly with the sorts of conditions and traits that Lippman and others had in mind. In response, important sociological work has focused precisely on the failure of the genes-for conditions, such as cystic fibrosis, to correspond perfectly to clinical diagnostic criteria as well as the liminal cases produced by this discrepancy (Hedgecoe 1998, 2000; Kerr 2000, 2004; Miller et al. 2006; Timmermans and Buchbinder 2011). But social scientists have still tended to assume something like the gene-for model, even if our main focus becomes its failure to work out neatly and the sociotechnical work done to clean up the mess. Even Paul Rabinow’s enormously influential formulation of biosociality only allowed for identity formation on the basis of genetic risk factors for existing conditions (Rabinow [1992] 1996), while Nikolas Rose’s molecular gaze (2007b) does not consider the possibility that genomics could provide a new basis for classifying illness rather than a new terrain upon which to explore existing conditions. One way or another, the social studies of science and medicine remain beholden to this outdated gene-for framework. So, how else might the juggernaut that is human genetics transform the way we understand human difference?

Genomic Designation

The categories that we use to understand one another have a profound impact on our lives. Take Ian Hacking’s notion of kinds of people or human kinds: categories that interact, or loop, with the people who are so classified in a way that dynamically transforms the categories, expert practices, and the people themselves (Hacking 1995, [1995] 1998b, 2007). Instead of reductionism, I argue, we need to start paying close attention to the way knowledge about genetic mutations can give rise to new kinds of people.

Increasingly, biomedical researchers are following the US National Human Genome Research Institute’s Grand Challenge II-3 in its call for a new molecular taxonomy of illness [to] replace our present, largely empirical, classification schemes (Collins et al. 2003:841; see also Check Hayden 2008; Insel 2013). In this vein, Loscalzo, Kohane, and Barabasi (2007:1) directly challenge the contemporary classification of human disease [which] dates to the late 19th century, and derives from observational correlation between pathological analysis and clinical syndromes. They argue for nothing less than redefining human disease in this postgenomic era. A genomic perspective can draw powerful distinctions between indistinguishable phenotypes and render previously unrelated ones deeply akin (see also Goh et al. 2007).

The turn to genomic classification is now firmly established in research fields that deal with developmental difference, where it briefly seemed to coalesce under the rubric of genotype-first discovery and diagnosis (Cody 2009; Ledbetter 2008, 2009a, 2009b; Saul and Moeschler 2009). A growing movement in psychiatry, not least the leadership of the National Institute of Mental Health, has called for their diagnostic system to be revised in accordance with biological etiology and genetics in particular (Insel 2013; Regier et al. 2009; Whooley and Horwitz 2013). In these and many other fields, the failure of the gene-for model has led researchers to reclassify illness in a way that starts with genetic mutations and works from there. But how does this work when the mutation is more or less clear, yet its effects are anything but? How does a category shape clinical practice, social action, and personal identity when the people who have the mutation in question could never have been grouped together on the basis of what they are actually like?

These are not hypothetical questions. Many biomedical experts, clinicians, patients, and health activists have already moved beyond a reductionist version of geneticization. They have adopted a radical strategy for mobilizing mutations that I propose we call genomic designation. Rather than relying on correlations with existing categories, they discover, delineate, and diagnose disease strictly according to observations of the genome. Sometimes, genomic designation takes place in the face of enormous phenotypic heterogeneity. To be clear, genomically designated conditions are not clinically diagnosable. Yet under certain conditions, they can give rise to specialist clinics and vibrant patient advocacy organizations. Furthermore, genomically designated conditions can be used to pry open far-reaching questions about human difference or, in other settings, to realign clinical judgment.

I discuss the concept of genomic designation in far greater detail in chapter 1. For now, a few important points of clarification: First, genomic designation can reclassify disease in many different ways. I devote the most attention to striking cases like 22q11.2DS, Fragile X syndrome and XYY syndrome, where knowledge about a mutation had a radical impact on medical classification. However, it is important to keep in mind that genomically designated conditions can have complex relationships to more long-standing clinical categories. Genomic designation can be used to lump, split, and recalibrate disease categories as well as create entirely new ones. Insofar as a mutation comes to be necessary and sufficient for a diagnosis, we are dealing with a genomically designated condition.

Second, genomic designation can be seen very powerfully in the classification of cancer (e.g., Venkitaraman 2002; for sociological studies on genomic oncology, see Bourret, Keating, and Cambrosio 2011; Nelson, Keating, and Cambrosio 2013), and even the delineation of species of bacteria (e.g., Rowan and Powers 1991; Zeaiter, Liang, and Raoult 2002). It also plays a central role in the classification of metabolic disorders: a recent Genetics in Medicine paper presented a nosology of 1,015 inborn errors of metabolism (and counting), all of them tied to mutations in specific genes. The authors were crystal clear: The involvement of different gene products is considered sufficient for separation into different entries, even if the phenotype is similar (Ferreira et al. 2018:table 1). However, I mostly ignore the way genetics has given us new categories of malignant growth, inabilities to metabolize food, or novel species of bacteria. Instead, I focus on the way mutations have been used to carve out new categories of human disease that almost always involve childhood developmental difference.

Finally, genomic designation simply refers to the practice of classifying human difference on the basis of genetic mutations. In the large majority of cases, it amounts to little more than a few papers on a new mutation and the syndrome it causes. I focus on the less common but more sociologically interesting cases where a mutation comes to mean far more than that. Whether, when, and how a mutation truly shapes people’s lives is always an empirical question—the central question that I grapple with throughout this book.

A Brief Note on Methods

Throughout this book I shamelessly focus on sites that embody the transformative potential of genomic designation. The point is not to mislead the reader: I freely acknowledge genomic designation is not the reigning mode of medical classification, and—despite major gains in just the last few years—it is unlikely to become dominant anytime soon. Rather, my aim is to examine the conditions, organizations, and people who exemplify genomic designation in order to show something new and important emerging at the intersection of genetics, medicine, and patient advocacy.

My primary method is qualitative, comparative-historical research. Using the record of published biomedical research, along with a variety of publicly available resources, archival materials, and oral histories, I outline the varied history of genomic designation as a way of classifying people over the last sixty years. My framework for comparing the way mutations have been mobilized across cases, places, and historical periods is discussed in detail in the next section. In addition, I use bibliometric analysis of the Institute for Scientific Information’s (ISI) Web of Science database at several points throughout the book in order to model the impact of genetics on nosology and assess the status of mutations in pertinent medical literatures.

The entire book also draws on IRB-approved fieldwork conducted at conferences and events for genetic disorders, primarily 22q11.2DS but also Fragile X syndrome and 22q13DS. During these conferences, I attended hundreds of presentations and breakout sessions by researchers, clinicians, patients, parents, and others, as well social events where they all mingled as a single community united by their mutation of interest. I conducted dozens of interviews with biomedical researchers, clinicians, advocates, and parents and visited carefully targeted sites where genomic designation is playing out, such as Elwyn Services, the Geisinger Autism and Developmental Medicine Institute, the MIND Institute at UC Davis, Children’s Hospital of Philadelphia, and a meeting of the US Department of Health and Human Services’ Secretary’s Advisory Committee on Heritable Disorders in Newborns and Children on newborn screening. Finally, I was also fortunate enough to have many illuminating, informal conversations with patients, parents, and allied experts during the course of this fieldwork that, while I cannot quote them directly, shaped this book in innumerable ways. All of these methods are discussed in further detail in the relevant chapters.

Writing the History of Mutations

What do I mean by a comparative-historical analysis of genomically designated conditions? In the simplest sense, it is the history of the genetic mutations that have been cast as novel disease entities in the human genetics literature. Dozens upon dozens of new medical conditions have been reported in the literature since 1959 according to the logic of genomic designation. However, the fate of those novel genetic conditions is radically uneven both within and across cases. Some never amount to much more than a case report or two, while others have become powerful categories of human difference underwritten by complex networks of research, treatment and social mobilization.

To be sure, mutations do not simply appear as distinct, fully formed abnormalities when researchers scrutinize people’s genomes (see Rabeharisoa and Bourret 2009; Hogan 2016; Timmermans 2017). Oftentimes, the mutations themselves start out as what Rheinberger (1997) calls epistemic things—objects that have no clear referent outside of the experimental system in which they first come into view and have the capacity to surprise researchers and redirect their work. Over time though, they are often largely stabilized or black-boxed (à la Latour 1988; Rheinberger 1997:30) and thereby turned into technical things that can be studied across labs and even different testing platforms. In this way, a mutation itself may cease to be an epistemic thing in the world of genetic testing. But that is only the end of the beginning. As Rheinberger argues (1997:30), science studies scholars tend to overlook black-boxing’s impact on a new generation of emerging epistemic things. Once they are rendered more or less stable as genetic test results, mutations can begin new and incredibly generative careers in many other fields ranging from molecular biology, neuroscience, and pharmaceutical development through medicine, clinical psychology, and special education. That is the sort of history I want to tell.

Simply knowing that a mutation exists does not get us very far. It is only after years of painstaking work and cooperation spanning an array of biomedical fields and stakeholders that a mutation comes to index a new kind of person. That is why even the same genetic mutations can mean very different things over time. A sociological analysis of genomic designation must therefore go beyond the fact that mutations can be stabilized as objects of knowledge, or even the fact that they can give rise to new syndromes in the literature. We need to examine how it is that those new categories matter to the way we understand and act on human difference. It must go beyond the field of human genetics, for which genetic classification came as an unproblematic turn once they were able to observe abnormal chromosomes. Instead, we need to examine how genomic designation has been taken up by researchers in other fields, clinical practitioners, commercial enterprises, media, advocates, and the diagnosed themselves. This section therefore outlines my framework for analyzing the historical conditions of possibility, processes of network formation, and forms of collective action that can turn a genetic mutation into a new kind of person, with all that means for the diagnosed and their families.

Reiterated Fact-Making

How can we explain the contrasting fates of mutations over time? For our purposes, the traditional comparative-historical logic is fatally undermined by the fact that even our comparisons between cases are far from independent or equivalent (Sewell 1996): many researchers and advocates are very much aware of and can often be found working with multiple genomically designated conditions, while the physiological implications of the different mutations themselves are often far from equivalent. Furthermore, when we are analyzing the shifting meanings of the same mutations over time, a conventional comparative logic is clearly a nonstarter.

In order to overcome these obstacles, I adopt a comparative approach that draws on what Jeffrey Haydu (1998) calls reiterated problem solving—a way to gain explanatory leverage by rethinking sequences of events across periods. Haydu offered reiterated problem solving as a comparative-historical tool that incorporates key insights from narrative and path-dependency approaches, but departs from them by examining how actors respond to similar problems or crises in different historical periods. He deftly applied it to the example of successive industrial-relations regimes in the twentieth-century United States. Rethinking the connections between events in different time periods as reiterated problem solving, Haydu explains, helps us to mak[e] use of continuities across periods, and [avoid] certain pitfalls of variable-based comparisons by putting historical particulars to explanatory work (341). This approach allows for the study of social action in different historical settings, the explanation of different outcomes, and careful attention to the way that settlements in one period constrain and enable actors working to solve a recurrent problem later on. Reiterated problem solving therefore holds great promise for a comparative study of genomic designation over the last half century.

However, we cannot really say that we are connecting events between periods through sequences of problem solving (Haydu 1998:349). Why not? Haydu rightly insists that in defining and delimiting recurring problems, one criterion must be the social actors’ own understandings (355). At this point, it seems as though we have reached something of an impasse. It is simply not the case that human geneticists in the 1960s and a parent advocate today would recognize a common dilemma, as Haydu put it,² even if their interest is in precisely the same genetic mutation. Even today, we find incommensurable formulations of the matter at hand. Mobilizing mutations was not a problem that competing groups fought over or that geneticists failed to solve, but an entirely new project or problematization (see Foucault 1990a:257) that had to be taken up by actors with very different orientations and expertise. Forging alliances with new groups of actors and rethinking the very matter at hand—that is, the problem to be solved—is central to the rise of genomically designated conditions.

What did remain constant across different times and places—or at least constant enough for a comparative analysis—were the mutations themselves. They are the unifying thread that allows for a comparative-historical analysis of genomic designation, not the actors and their conceptions of what to do with them. The shifting ways in which we understand and use knowledge about those mutations is largely explained by changes in the networks of actors assembled around them. As much as the fields of human and medical genetics exhibit significant continuity over the half century covered in this book, we cannot remain focused on geneticists if we want to understand how conditions like 22q11.2DS, 5p− or