“I CONTAIN MULTITUDES”: CHIMERAS, CELLS AND THE MATERIALIZATION OF IDENTITIES A Dissertation Presented to the Faculty of the Graduate School of Cornell University in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy by Aryn Martin August 2006 © Aryn Martin 2006 “I CONTAIN MULTITUDES”: CHIMERAS, CELLS AND THE MATERIALIZATION OF IDENTITIES Aryn Martin, Ph.D. Cornell University 2006 This dissertation traces the biomedical networks through which human chimeras are clinically constituted. Chimeras are organisms in which two or more genetically distinct cell populations co-exist. Unlike their experimentally produced counterparts (often interspecies mixtures), human chimeras arise spontaneously when fraternal twin embryos fuse in the womb. While undoubtedly a rare occurrence, the true incidence is unknown because many chimeras have no visible signs of their composite being. Hence, chimeras are produced in an inadvertent encounter with the laboratory, during blood donation or tissue typing, for example. A subtype of chimerism, called microchimerism, occurs when the second cell population is tiny. The main context in which microchimerism is discussed in biomedical research is cell exchange between women and their fetuses, now thought to be a normal event during pregnancy. Human chimerism has existed since the 1950’s, and microchimerism has become a research theme only in the last decade. Like multiple personality disorder, conjoined twinning and organ transplantation, human chimerism troubles the connection between the individual and the body. Bodies, in these cases, are not neatly contained, which calls into question the inevitability and naturalness of singular embodiment. Chimerism, in particular, offers an analytical vantage point for the examination of genetics and identity in contemporary biomedicine. Using historical and ethnographic methods, and analytical tools from science & technology studies, this dissertation explores human chimerism and microchimerism. Interviews with scientists and careful analyses of published and unpublished literature reveals that biomedical researchers speak and write as though cells and people are interchangeable; not only do people contain cells, cells contain people. This tendency is an instantiation of genetic reductionism (we are our genomes), but it also refers to much older Western traditions wherein the material of the body is one and the same as the person. In chimerism, though, ascribing personal identity to cells leads to a confusion of the boundaries by which individuals are normally separated. While the location of personhood in cells is no doubt a reductionist tendency, the result – the fragmentation and interspersion of selves – leads to a provocative anti-reductionist conclusion: we all contain multitudes. BIOGRAPHICAL SKETCH Aryn Martin received her B.Sc.H. from Queen’s University in Kingston, Ontario in 1996. Her honors thesis, “Diagnosis of Monosomy 18 Mosaicism using Fluorescence In Situ Hybridization of Bladder Exfoliate Cells,” won the Queen’s Pathology award for the highest standing on an undergraduate thesis. After six months working on women’s health policy in Johannesburg South Africa, she began graduate work at York University, Toronto, in women’s reproductive health and international development. In 1999, she was awarded a Masters in Environmental Studies. During her Masters work, a change of interests and influences led her to the social studies of science and back to her roots in genetic medicine. In 2000, she moved to the United States, and began a combined M.A./Ph.D. program in Science & Technology Studies at Cornell University, receiving her M.A. in 2003 and her Ph.D. in 2006. She will begin teaching as an Assistant Professor of Sociology at York University in Toronto. iii For my parents and my brother, whom I contain iv ACKNOWLEDGMENTS I am unabashedly the opposite of a rugged individualist, and so the people who have sustained me during this project are many. I am most grateful to my supervisor Michael Lynch, whose rare combination of humility, brilliance and compassion are an inspiring example of how to enrich an academic, or any, community. Since the beginning of my time at Cornell, we have been engaged in an ongoing conversation; whether it is about counting, chromosomes or fly-fishing, I always profit from Mike’s unique insights. His cautious embrace of this project, even when it was fledgling and unformulated, allowed me to press on. Stephen Hilgartner has also been a constant support during my graduate training, and during this project. I am thankful for his encyclopedic knowledge of genetics and of S&TS. It was Steve who first told me about fetal cells in maternal blood; this and other snippets from our conversations would inevitably route and reroute my research. My newest committee member, Rachel Prentice, influenced my work at a formative time. It was invaluable to me to have a confidant who so recently went through the processes of writing and defending a dissertation, and she delivered advice with kindness and with tea. Others who taught and challenged me at Cornell include Anna Marie Smith, Elizabeth Toon, Ron Kline, Trevor Pinch, Christine Leuenberger, Hélène Mialet, Peter Dear and Michael Dennis. The faculty, students and staff in the department contribute to a vibrant intellectual culture. For their collegiality and friendship, I am especially grateful to: Park Doing, v Christina Dunbar-Hester, Lisa Jacobsen, Javier Lezaun, Anna Maerker, Cyrus Mody, Deb Van Galder, Janet Vertesi, Heidi Voskuhl, and Judy Yonkin. I would not have arrived at this project, let alone this doctorate, had I not encountered three extraordinary mentors along the way. At Queen’s University, I was privileged to study with Annette Burfoot and Alessandra Duncan. During my senior year, I simultaneously studied the sociology of reproductive health with Annette and cytogenetics with Alessandra, and it was this temporal coincidence that made me a science and technology studies scholar, though long before I knew it. Joan Steigerwald, my Masters supervisor at York University, introduced me to S&TS and gave me the courage to apply to Ph.D. programs worldwide. Her example of adept interdisciplinarity and rigorous scholarship has given me a model to which to aspire. I am happy to have ongoing relationships with each of these women, and I deeply value their continued interest in my work. I am grateful to the National Science Foundation for supporting this work with a Dissertation Research Award, which allowed me to travel extensively to connect with interviewees and to attend conferences.1 During this project, I also received support from the Social Sciences and Humanities Research Council of Canada, and from the journal Social Studies of Science, for which I worked as an editorial assistant. 1 NSF Award #0432120, “I contain multitudes”: Genetic chimeras and material negotiations of identity, August 1, 2004-August 1, 2006. vi Like any social scientist, I am profoundly indebted to my research subjects. They happily volunteered time and information, and they received my interest in their work with patience and generosity. These include parents and children of the International Mosaic Down Syndrome Association; physicians and scientists in the related fields of chimerism, fetal cell research and microchimerism; and cytogeneticists and technologists at the Montreal Children’s Hospital. While they may not have impacted the content of the research directly, family and friends certainly have impacted the content of the researcher. I thank my parents, Judie and Peter Martin, whose faith in their children is boundless. My mother has taught me much, not the least of which is the importance of telling stories and listening to them, which is the heart of this work. My father’s quiet confidence in me is an unwavering source of strength. I thank my brother, my oldest friend, for reminding me that getting a Ph.D. doesn’t mean I can get away with being highfalutin’. I am most fortunate to have multitudes in my family – the Morrises and the Martins – who have been there since the beginning, cheering me on. The Bronsons have recently, though no less enthusiastically, taken up the role as my more local mishpocha. I am grateful to my friends Janet Swoger- Ruston, Mary Simms, Alyson Parker and Vicki Toscano with whom I sort through the layers of life, love and work, which are never truly separate. Finally, Eric Bronson fortified my soul in countless daily ways. He is my reader, my rescuer, my song and dance man. Without him, everyone else on this list would have had a much tougher job. vii TABLE OF CONTENTS BIOGRAPHICAL SKETCH................................................................ iii ACKNOWLEDGMENTS...................................................................... v TABLE OF CONTENTS.................................................................... viii LIST OF FIGURES .............................................................................. xi LIST OF TABLES ............................................................................... xii INTRODUCTION.................................................................................. 1 THE CATEGORY OF THE PERSON .............................................................. 1 THE CASE: HUMAN CHIMERISM............................................................... 3 1) Chimeric twins and singletons....................................................... 4 2) Fetal microchimerism...................................................................