The precautionary principle traditionally summarized as “first, do no harm” should not be reduced to “first, do nothing,” especially regarding technological fixes for our deteriorating biosphere and economy.
If the cause of the bio-decay is population growth, which, in turn, is due to technology, then the idea of fixing it with technology merits a heavy dose of humility and reflection. Many technological developments “seemed like a good idea at the time” but had huge unintended consequences: Irrigating crops led to malaria; riverside settlements led to cholera; insect management led to a birdless silent spring; fertilizer led to microbial blooms and fishkills; and so on.
Despite such risks, technological paralysis is not an option if our civilization is to endure and flourish. We must face the challenges posed by melting ice caps, massive famines, entrenched pandemics, emerging diseases, and a host of other threats. Of the many proposed technological solutions for these ills, each bears its own potential for inadvertent disaster — and a requisite, complicating need for safeguards that can be prohibitively expensive. But what if a technology’s safeguards could directly enhance its capabilities to address our global problems? Ironically, this may be the case for one of the most feared and misunderstood advancements in recent years: biotechnology.
Life itself is the most powerful technology of all, a technology developed and honed not through orderly procedures in a laboratory but through billions of years of trial and error by natural selection. To date, the revolution in biotechnology has allowed us to harness the power of living things in ways never before possible, but the precautionary principle has precluded its use in many instances. Now, we stand on the brink of developing transformative methods that could make biotechnology not only safer but more useful against some of the world’s most pressing problems.
Consider the problem of global warming, caused by rising levels of atmospheric carbon dioxide (CO2). Even if we achieve huge successes with energy conservation and alternative energies like wind, nuclear, and solar, this won’t lower existing CO2 levels. To do that, we need to capture CO2 from the atmosphere and sequester it. We could spend money (and energy) pumping CO2 to some inaccessible site like the ocean floor, but the political determination to do so may be hard to muster. On the other hand, we could co-opt biological processes to sequester the CO2, potentially even folding it into useful products like plastics, roads, and buildings. Nature sequesters massive amounts of CO2 all the time: About 15 percent of the total 2 x 1012 tons of atmospheric CO2 is removed each year by processes like photosynthesis. But most of that CO2 returns to the atmosphere at the same rate, liberated from the decomposing bodies of the “biobuilders” (animals, plants, etc.) by the “bio-destroyers” (mostly parasitic viruses and microbes). This evolutionary arms race between growth and decay has raged since the dawn of life; if we could find a way to give the builders even a slight edge, sequestering a lot more CO2 would be just one of many potential applications.
Let’s start with the viruses. Viruses seem biologically unbeatable because they can tolerate much higher mutation rates and can reproduce much faster than their host organisms. So every evolutionary strategy that the host may try is immediately countered by many viral changes. To circumvent this, we’d have to place the host in isolation and protectively alter it in a way that no amount of viral mutation could overcome. But what Achilles heel could all viruses share? They show enormous diversity — indeed, no gene is universal to all viruses, whereas all cells share hundreds of genes. Every virus does, however, expect its host to allow it to reproduce.
One crucial step in the reproduction of all viruses (and provided only by the cell) is protein synthesis, the assemblage of proteins from a set of 20 different amino acids. Protein synthesis proceeds according to the universal DNA translational code, which allows a cell to read the nucleotide bases (A, C, G, T) on a strand of DNA three at a time to determine which amino acid goes where within a protein. These DNA triplets are called “codons.” A little arithmetic reveals that the translational code is redundant: The number of possible triplet combinations of the four DNA bases is 64, so there can be one, two, four, or even six codons per amino acid (there are also three codons set aside for telling the cellular machinery to stop making a specific protein).
