quarta-feira, 29 de novembro de 2017

Genetica

"For more than a century, the concept of the gene has dominated biological science in the global North. Built on thousands of years of plant cultivation and animal husbandry—the original experimental biology—which itself followed hundreds of thousands of years of observational biology by hunter-gatherers, the rise of genetics was simultaneously a window into the inner workings of living systems and a hostile takeover of all biological knowledge that preceded it.
"But despite its grip on the scientific culture of affluent societies, the gene’s reign as the supposed “secret of life” is coming to an end. The more we learn about natural systems—or, in many cases, relearn what was known traditionally—the clearer it becomes that genes are only one class of factors that causes development (changes that turn embryos into fully formed animals and plants) and evolution (transformation of simple organisms into more complex ones over the history of life). Alarmingly, however, even as the notion of the all-powerful gene loses scientific relevance, it is gaining new ideological traction in the appropriation and privatization of resources, helping to foster inequality among ethnicities and socio-economic classes. How this has occurred, and what can be done to stop it, is the subject of this article.
"In 1931, the Soviet historian of science Boris Hessen described how Isaac Newton’s laws of motion, seemingly universal landmarks in our understanding of the physical world, were produced partly in response to the technical needs of the emerging English industry of the seventeenth century. Correspondingly, the theory was infused with the ideology of its era, and its static worldview presented obstacles to further advances. Hessen showed how scientific analysis of nonmechanical matter (he focused on thermodynamics, but his arguments also pertain to chemistry and biology) was impeded by the Newtonian paradigm. Even the concept of conservation of energy, a straightforward mathematical consequence of Newton’s laws of motion, was not articulated until after Newton’s death. This was likely an effect of early Newtonian theory’s undialectical character: only point masses were considered, and both dissipation (the degradation of energy) and nonmechanical productive practices, such as metallurgy or steam power, were excluded.
"Ever since Hessen (and by extension, Karl Marx and Frederick Engels, whose philosophy inspired his analysis) it has no longer been possible for honest observers of science to ignore its ideological dimension. Certainly this applies to the gene. When Gregor Mendel conducted his plant breeding experiments in nineteenth-century Moravia, he employed methods essentially the same as those used by farmers for millennia. By recording his results quantitatively, he discovered consistent associations of “factors” (what we now call “genes”) carried by the plants’ seeds with choices exerted later in development between alternative traits, such as long or short stems, inflated or constricted pods. Simple reflection indicates that those who first produced maize from teosinte-family grasses in Mexico about 9,000 years ago were not stumbling on things randomly, but doing much the same as Mendel: breeding by selection and hybridization while carefully keeping track of the results, probably using the Mesoamerican record-keeping systems that were famously employed in calendars, astronomy, and large engineering and civic projects.
"Early farmers thus implicitly recognized and adapted Mendel’s factors long before he or European civilization existed. What was at stake in traditional agriculture, however, were the properties of whole organisms (i.e., maize plants) in the context of their conditions of cultivation. Variations in external conditions such as temperature, humidity, or soil quality can elicit disparate phenotypes—structures and functions—as surely as genetic variation does. Furthermore, favorable forms were propagated socially, via families and communities, rather than commercially (as was increasingly the case in the North), and in multiple varieties, rather than as the monocultures compelled by industrial standardization. Among the peoples who brought these crops into being, preservation of “ecophenotypic” variety (that is, the range of phenotypes in their different ecological settings) was the paramount scientific value. They thus had little reason to attribute the vital nature of maize to hidden elements at its smallest and most quiescent stage of development."

Stuart A. Newman is a professor of cell biology and anatomy at New York Medical College and a founding member of the Council for Responsible Genetics. For…
monthlyreview.org

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