Dissertation Research: "I contain multitudes": Genetic chimeras and material negotiations of identity

这篇科学和技术研究论文改进格兰特使用人种学和历史研究方法来追踪遗传马赛克和嵌合体的出现和特征。我们将对四例人类基因多发性进行比较。在每一种情况下，遗传上不同的细胞群体在人体内共存，或者在身体之间旅行(这让人质疑身体的概念)。自发的人类嵌合体来自子宫内异卵双胞胎之间的组织交换，或者是胚胎在发育早期的完全融合。基因马赛克是单细胞突变的结果，这种突变持续存在于改变后的细胞系中，该细胞系在生物体中与原始细胞群一起增殖。术语微嵌合体描述了胎儿细胞和DNA分子在母体中的持久性，以及母体细胞在孩子体内的持久性，这两种细胞在怀孕后仍然存在。微嵌合体也指器官接受者的一种情况，在这种情况下，供体细胞增殖并持续存在。本文利用这四个遗传多样性的案例(嵌合体、嵌合体、胎儿微嵌合体和移植微嵌合体)，在人类基因是独特的和离散的这一前提的历史和文化特殊性的基础上，获得了经验性和批判性的购买。换句话说，目标是密切和批判性地关注这样一个观点，即个人身份必然与唯一和单一的基因组联系在一起。在当代生物医学和生物政治中，基因和身份认同正变得越来越混为一谈，但从基因到自我的链条既不是不可避免的，也不是不可侵犯的。该项目的田野工作探索临床和实验情况，在这些情况下，人类被构建为多个基因。研究镶嵌和嵌合现象的实验室研究人员和技术人员将细胞和分子分为男性和女性、正常和病理、母体和胎儿、动物和人类以及自我和其他几个不同的类别。这个项目考察了微观层面的遗传同一性和整体层面的人类自我是共同产生和相互稳定的这一命题。大多数情况下，少数细胞的基因同一性(例如在法医检测和产前筛查中)可以与一个自给自足的个体重叠。这项研究中的案例提供了一个机会来探索在什么情况下遗传异质性扰乱了个性和身份的概念。与这种关系相反，该项目还研究了个体和身份的社会政治概念是否被编织到实验室中细胞和分子的遗传身份的实际分配中。NSF基金将支持美国、加拿大和英国的实验室、诊所、会议和支持团体的田野工作，在这些团体中，关于基因马赛克和嵌合体的知识被生产、谈判和争夺。将与每个研究界的调查人员和技术人员进行面谈。挑战他们被归类为怪物、边缘或混血儿的方式的耐心活动人士也将接受采访。参与者人种学研究将在几次会议上进行，来自不同社区的研究人员聚集在一起，讨论与构建人类遗传特性和多样性有关的紧急技术和医学问题。本论文项目的智力影响主要是在遗传学和身份的社会研究领域，关于生物科学性和世俗激进主义的实证工作，以及对遗传学的本质主义或决定论概念的理论批评。作为一门关于自我和多样性的研究，在技术实践中，它是对自我、碎片化和多样性的理论文献的补充。这项研究的更广泛的影响和影响涉及到那些与其身份的生物医学特征作斗争的个人和群体。这些人体内多种生物特性的共存可能为对人进行分类和排除提供了体制和官僚基础。此外，微嵌合体研究表明，我们在某种程度上都是遗传分布的。该项目将对关于基因鉴定的政治和技术辩论作出重要和及时的贡献；这些辩论既使基因个体具体化，具有讽刺意味的是，也助长了例外情况的激增。

This Science and Technology Studies Dissertation Improvement Grant uses ethnographic and historical research methods to trace the emergence and characterization of genetic mosaics and chimeras. Four cases of human genetic multiciplicity will be compared. In each case, genetically different cell populations co-exist in a human body, or travel between bodies (calling into question the very notion of a body). Spontaneous human chimeras result from tissue exchanged between fraternal twins in utero, or the complete fusion of embryos early in development. Genetic mosaics result from a single-cell mutation, which persists in an altered cell line that proliferates in the organism's body alongside the original cell population. The term microchimerism describes the persistence of fetal cells and DNA molecules in the maternal body, and maternal cells in the child's body, both of which persist after pregnancy. Microchimerism also refers to a condition of an organ recipient in whom donor cells proliferate and persist. This dissertation uses these four cases of genetic multiplicity (chimerism, mosaicism, fetal microchimerism and transplantation microchimerism) to gain empirical, and critical, purchase on the historical and cultural specificity of the premise that humans are genetically unique and discrete. In other words, the aim is to focus closely and critically on the idea that individual identity is necessarily bound to a unique and singular genome. In contemporary biomedicine and biopolitics, genetics and identity are becoming increasingly conflated, but the chain from genes to selves is neither inevitable nor inviolable. Fieldwork for this project explores clinical and experimental situations in which humans are constructed as multiple, genetically. Laboratory researchers and technicians concerned with mosaic and chimeric phenomena sort cells and molecules into discrete categories of male and female, normal and pathological, maternal and fetal, animal and human, and self and other. This project examines the thesis that genetic identity on the microscopic level and human selves on the holistic level are co-produced and mutually stabilized. Most of the time, the genetic identity of a few cells (such as in forensic testing and prenatal screening) can be made to overlap with a self-contained individual. The cases in this study offer an opportunity to explore circumstances in which genetic heterogeneity disrupts notions of individuality and identity. Reversing this relationship, the project also examines whether socio-political notions of individuality and identity are woven into the practical assignment of genetic identity of cells and molecules in the laboratory. NSF funds will support fieldwork in the United States, Canada and the U.K., at laboratories, clinics, conferences and support groups in which knowledge about genetic mosaics and chimeras is produced, negotiated and contested. Investigators and technicians in each of the research communities will be interviewed. Patient activists who challenge the ways in which they are classified as monstrous, marginal or hybrid also will be interviewed. Participant ethnographic research will be conducted at several conferences at which researchers from different communities come together and discuss emergent technical and medical issues associated with the construction of human genetic identity and multiplicity. The intellectual impact of this dissertation project primarily is in the areas of social studies of genetics and identity, empirical work on biosociality and lay activism, and theoretical criticisms of essentialist or determinist notions of genetics. As a study of selfhood and multiplicity identified with the very material of the body and in technical practice, it supplements theoretical literatures about the self, fragmentation, and multiplicity. The broader impact and implications of this study have to do with individuals and groups who contend with biomedical characterizations of their identities. The coexistence of multiple biological identities in these individuals may provide institutional and bureaucratic bases for classifying and excluding persons. Furthermore, microchimerism research suggests that we are all genetically distributed at some level. This project will make important and timely contributions to political and technical debates about genetic identification; debates that both reify the genetic individual and, ironically, contribute to the proliferation of exceptions.