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Although clonality is often discussed in reference to whole organisms, the phenomenon also applies to (and is underlain by) genetic processes operating within each individual. All forms of clonal reproduction begin with the faithful replication of genetic material. This chapter discusses the clonal propagation of nucleic acids (via DNA replication) and of entire nuclear genomes and chromosome sets (via mitosis) in populations of somatic cells. It also describes how mitochondrial genomes, as well as particular kinds of sex chromosomes, provide special examples of genetic systems that abstain from recombination. The net result of such micro-asexual processes is a multicellular individual, which can thus be viewed as a tightly knit colony of clonemate cells.

The birth of Dolly, a lamb born at the Roslin Institute in Scotland, created a wave of talk and commentaries from experts in the fields of ethics, religion, law, and medicine in 1997. Dolly was the first mammal successfully born as a result of cloning, using the technique somatic cell nuclear transfer. This chapter presents an in-depth look into the events prior to and the aftermath of the birth of Dolly, including how news on such “new biology” was related to the public.

The size–complexity hypothesis proposes that social group transformation (emergence of complex, individualistic groups) occurs when group size increases. Complex social groups exhibit a high degree of both reproductive division of labour (e.g., germline segregation, queen–worker dimorphism) and non-reproductive division of labour (e.g. many somatic cell types, worker polymorphism). It is proposed that, in multicellular organisms and eusocial societies, larger group size leads to the germline and the queen, respectively, acquiring virtual dominance. Since the virtual dominant is the group member to whose offspring groupmates have the highest mean relatedness, this explains why larger group size promotes increased reproductive division of labour. It promotes increased non-reproductive division of labour by permitting higher efficiency without compromising robustness. Enhanced division of labour and falling costs of within-group conflict allow larger groups to become more productive, and so, through positive feedback, promote further increases in group size and hence greater social complexity and individuality.

In this dialogue, Dr. Rebecca Franklin discusses with Janet Richfield, a stem cell scientist, and Beverly Simpson, who has been living with type 1 diabetes her entire life, the progress in clinical trials involving personalized embryonic stem cells that eventually could lead to a cure for Simpson's diabetes. Richfield, Simpson's endocrinologist, is working on producing islet cells that can be transplanted to diabetics to cure their insulin deficiency. Here they talk about the promise of stem cell research in the treatment of type 1 diabetes; where stem cells come from and how they work; how personalized embryonic stem cells are going to help diabetics like Simpson; the process of somatic cell nuclear transfer (SCNT); and the risks involved in SCNT.

In this dialogue, Dr. Rebecca Franklin and Dr. Frederick Jones, a stem cell biologist, discuss the prospects of cell reprogramming for producing therapeutic stem cells. The process of reprogramming an adult cell to its pluripotent stem cell origins, sometimes referred to as “dedifferentiation,” creates what are called induced pluripotent stem cells (iPSCs). The first evidence of this type of reprogramming from mouse cells was provided by Shinya Yamanaka and his colleagues at Kyoto University in Japan in 2006. Jones has invested considerable time reprogramming somatic cells to make them into embryonic stem cell-like cells (pluripotency). Franklin questions him about reversing the development of a differentiated cell, drawing on her knowledge of epigenetics and cellular biology. Here they talk about the possibilities for creating iPSCs from somatic cells that are more like their embryonic counterparts; oncogene expression and tumorigenesis in embryonic stem cells; and roadblocks to regenerative medicine involving iPSCs.

In this dialogue, Dr. Rebecca Franklin and Dr. Howard Chadwick, director of the National Center for Stem Cells within the (fictional) National Institutes of Health, discuss the ethics of cloning. The purpose of the National Center for Stem Cells is to help integrate regenerative medicine into the work of all the institutes. Chadwick is caught between a rock and a hard place with regard to embryonic stem cells: he recognizes their potential in science as well as the political firestorm they have produced. Here he and Franklin talk about the distinction between cloning human beings and using somatic cell nuclear transfer (SCNT) to create embryos for research; the distinction between therapeutic and reproductive cloning; and the issue of extracting embryonic germ cells from human embryos.

Chapter 5 examines the politics surrounding George W. Bush’s embryonic stem cell policy, and in particular debates over what terms should be used in public debate about human cloning. It examines the approach of the President’s Council on Bioethics to ground its deliberations in a shared language that would open up space for ethical disagreement, rather that limit it in the name of producing consensus. The Council’s project of finding a common language was appropriated by a group of scientists who set about to reform the language employed in public deliberation.

This chapter analyzes the intricacies of cloning policies in the United Kingdom, Italy, and the United States. It compares three national approaches to dealing with clones derived from somatic cell nuclear transfer. It evaluates the place of human life in three national sociotechnical imaginaries. The chapter shows that in its relation to biotechnological change, Italian political culture seems to be structured around the secular/religious and the natural/artificial dichotomies. It suggests that the juxtaposition of the three cases of the making of clones highlights how political cultures are integral to the development of technoscientific objects.

Having mapped the scope of human chromosome studies in the postwar era, chapter 5 addresses the relation between microscope-based and molecular approaches to human heredity. In particular, it reconsiders what is often referred to as the molecularization of chromosome research in the light of the simultaneous turn of molecular biology to human and medical genetics, a field long occupied by chromosome researchers. The chapter focuses on two areas of overlapping interest: the molecular biologists’ concern with the structure and function of chromosomes and the cytologists’ focus on gene mapping, a practice now often associated with genomic science. Chromosome banding and somatic cell hybridization techniques allowed cytogeneticists to map thousands of genes before molecular techniques started making an impact. The organization of the Human Genome Project in many ways built on the work and organization of the Human Gene Mapping Workshops, convened by cytogeneticists starting in the the early 1970s. The chapter concludes with a consideration of the epistemic and historical commonalities between the two contending approaches. In particular, it considers the increasing role of fluorescent microscopic techniques such as FISH (fluorescent in situ hybridization) in cell and molecular biology that provides a common ground for the two endeavors.

This chapter analyzes August Weismann's theory of germinal selection—a process of competition and selection among the hereditary units within the germplasm. He argued that the germ line was not affected by the changes undergone by the somatic cells during the organism's lifetime and that heritable adaptive evolutionary changes resulted from the operation of natural selection on individuals, a form of selection that he called “personal selection”. The chapter examines the problems that challenged Weismann's original focus on personal selection and explains how he interpreted them in terms of his germinal selection theory.

The long history of the use of animal embryos in biomedical research has recently been revolutionised by the so-called cloning or nuclear transfer technique. In contrast to the traditional in vitro fertilisation, obtained with the union of an ovum and a sperm, animal embryos are produced by inserting the engineered nucleus of a somatic cell, for example a mammary gland cell, into an enucleated ovum. According to this chapter, it has long been recognised that biological evolution by natural selection is predicated on the uniqueness of the biological make-up of the individual and the resulting variability among individuals in sexually reproducing populations. It suggests that it is time to acknowledge that a non-genetic inborn variability between the brains of different individuals may in turn help the cultural evolution of the species, by the chance production of the cerebral primordia of exceptionally gifted minds, to be nurtured in appropriate environments.

To understand the evolutionary consequences of poor coadaptation of mitochondrial and nuclear genes, it is necessary to consider in molecular detail the manifestations of mitochondrial dysfunction. Most considerations of mitochondrial dysfunction resulting from mitonuclear incompatibilities focus on protein–protein interactions in the electron transport system, but the interactions of mitochondrial and nuclear genes in enabling the transcription, translation, and replication of mitochondrial DNA can play an equally important role in mitonuclear coevolution and coadaptation. This chapter reviews the extensive literature on how mitochondrial dysfunction is the cause of many inherited human diseases and explains how this biomedical literature connects to a rapidly growing body of research on the evolution and maintenance of coadaptation of mitochondrial and nuclear genes among non-human eukaryotes. The goal of the chapter is to establish the fundamental importance of coadaptation between co-functioning mitochondrial and nuclear genes.