CHAPTER 6 GENE THERAPY |
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A decade before stem cells began to reach the front page, the next big thing in medical applications of genetic technologies was supposed to be gene therapy. So far, it hasn't worked out. There have been tragic deaths and very few signs of hope.
Despite to some extent, even because of this failure, some people have proposed introducing genetic changes that would affect our children directly. So far the Federal authorities have refused to entertain such proposals, but there are worrying signs that they may change their minds. And all this high-cost, high-tech research is happening at the same time as US healthcare costs are soaring and standards are falling, compared with the rest of the world. Scientifically and socially, gene therapy still has more questions than answers. This chapter's section titles, below, are followed by
There are many more resources in the Appendix. |
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INTRODUCTION
GENE THERAPY IN THE 1990S: THE NEXT FALSE DAWN OF MARKETS AND MEDIA LEARNING THE WRONG LESSONS IN UTERO SOMATIC GENE TRANSFER PROPOSAL THE INDIVIDUAL AND SOCIETY FURTHER READING BOX 6.1 Somatic vs. Germline GE BOX 6.2 The Jesse Gelsinger Tragedy BOX 6.3 Hi-Tech Treatments for Baldness BOX 6.4 Short People BOX 6.5 Media Approaches: |
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If a bad gene were to cause a disease, and you could replace the gene, wouldn't that be great? You'd have not just a treatment but a cure. And what if you had inherited an adequate but less-than-ideal gene? Swap that one out and you'd be ... better than well! Things are not nearly so simple (see Chapter 2) but that's the principle behind the hope of what is called "gene therapy" and the perhaps more imminent hazard of "gene doping" in sports (see Chapter 7). Some people even seem to think these techniques may lead to eternal, or at least extended, life. "Gene therapy" is really a misnomer: So far, there have been hundreds of experiments but very little success and no therapies. The term is also used rather loosely to cover several different kinds of interventions, some of which involve not replacing genes but turning them on or off. Still, there is enormous power in a simple and comprehensible story (see Chapter 4, on stem cells), and the term is entrenched. Even if it is somewhat misleading, there's no avoiding it. The very failure of gene therapy ironically increased the pressure from some quarters to attempt the fully-fledged human genetic engineering of children, as discussed in more detail below. If somatic interventions (see Box 6.1) are hard to control because you have to change so many cells, then germline ones, in which you only have to modify one single cell (or very few) might be more achievable. ... |
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There is a crucial distinction between somatic and germline genetic engineering, or "therapies" as advocates of Human GE like to call them. It is discussed in more detail in Chapter 2, but briefly:
"Germ cells" are eggs, sperm and the cells that make them; they pass on genes to offspring, and this shared lineage from parent to child is known as the "germline" of the organism or, more broadly, the species the continuous inheritance from ancestor to descendant. "Somatic" comes from the Greek for "body" and may be used to contrast either with the psyche or with the germ cells, depending on context. In GE contexts, somatic interventions only affect one particular body. Intentional Human GE would of course be done in the lab, using very early embryos and IVF techniques, not the germ cells of adults. However, because gene transfer is not an exact science, some kinds of intervention that are meant to be somatic may also, by mistake, affect the germ cells. If they do, they could be passed on to children and thus affect the germline. One controversial proposal that admittedly risks this, perhaps in a deliberate attempt to push the envelope, is discussed later in this chapter. |
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Links were checked and functioning as of 5/09/05; they are supposed to open in new windows. Please report broken ones. Stephen Leahy, "The Genetics Revolution Has Failed to Deliver," Macleans, 09/30/02, is a succinct, skeptical overview. The Food and Drug Administration (FDA)'s Center for Biologics Evaluation and Research (CBER) posts the text of warning letters sent to researchers, such as the one connected with the Gelsinger case. It also posts articles on the role of the FDA in regulating gene therapy, and this valuable, although by now somewhat outdated, overview: "Human Gene Therapy: Harsh Lessons, High Hopes," by Larry Thompson, FDA Consumer magazine, September-October 2000 The Recombinant DNA Advisory Committee (RAC) also has some regulatory authority over gene transfers. The Council for Responsible Genetics (CRG) has called for a moratorium on gene therapy trials. The National Cancer Institute has an overview of gene therapy, almost all of which applies to more than just cancer. The Genetics and Public Policy Center (GPPC) also has an introduction to the issue. The American Society of Gene Therapy (ASGT) remains hopeful. Its website carries position statements and even offers golf shirts, in medium or large, for only $25 plus $5 shipping. |
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