Amazing Article on Viruses
I was e-mailed an article from The New Yorker about mankind's continued battle against viruses. It's incredibly insightful, but also very long. I suggest you read the whole thing, but I'll only post a few choice quotes from the article here:
"Nothing — not even the Plague—has posed a more persistent threat to humanity than viral diseases: yellow fever, measles, and smallpox have been causing epidemics for thousands of years. At the end of the First World War, fifty million people died of the Spanish flu; smallpox may have killed half a billion during the twentieth century alone. Those viruses were highly infectious, yet their impact was limited by their ferocity: a virus may destroy an entire culture, but if we die it dies, too. As a result, not even smallpox possessed the evolutionary power to influence humans as a species—to alter our genetic structure.
That would require an organism to insinuate itself into the critical cells we need in order to reproduce: our germ cells. Only retroviruses, which reverse the usual flow of genetic code from DNA to RNA, are capable of that. A retrovirus stores its genetic information in a single-stranded molecule of RNA, instead of the more common double-stranded DNA. When it infects a cell, the virus deploys a special enzyme, called reverse transcriptase, that enables it to copy itself and then paste its own genes into the new cell’s DNA. It then becomes part of that cell forever; when the cell divides, the virus goes with it.
Scientists have long suspected that if a retrovirus happens to infect a human sperm cell or egg, which is rare, and if that embryo survives—which is rarer still—the retrovirus could take its place in the blueprint of our species, passed from mother to child, and from one generation to the next, much like a gene for eye color or asthma.
When the sequence of the human genome was fully mapped, in 2003, researchers also discovered something they had not anticipated: our bodies are littered with the shards of such retroviruses, fragments of the chemical code from which all genetic material is made. It takes less than two per cent of our genome to create all the proteins necessary for us to live. Eight per cent, however, is composed of broken and disabled retroviruses, which, millions of years ago, managed to embed themselves in the DNA of our ancestors."
and this:
"Because they no longer seem to serve a purpose or cause harm, these remnants have often been referred to as “junk DNA.” Many still manage to generate proteins, but scientists have never found one that functions properly in humans or that could make us sick.
Then, last year, Thierry Heidmann brought one back to life. Combining the tools of genomics, virology, and evolutionary biology, he and his colleagues took a virus that had been extinct for hundreds of thousands of years, figured out how the broken parts were originally aligned, and then pieced them together. After resurrecting the virus, the team placed it in human cells and found that their creation did indeed insert itself into the DNA of those cells. They also mixed the virus with cells taken from hamsters and cats. It quickly infected them all, offering the first evidence that the broken parts could once again be made infectious. The experiment could provide vital clues about how viruses like H.I.V. work. Inevitably, though, it also conjures images of Frankenstein’s monster and Jurassic Park."
and finally:
"The Nobel Prize-winning biologist Joshua Lederberg once wrote that the “single biggest threat to man’s continued dominance on this planet is the virus.” Harmit Malik, an evolutionary geneticist at the Fred Hutchinson Cancer Research Center, acknowledges the threat, yet he is confident that viruses may also provide one of our greatest scientific opportunities. Exploring that fundamental paradox—that our most talented parasites may also make us stronger—has become Malik’s passion. “We have been in an evolutionary arms race with viruses for at least one hundred million years,’’ he told me recently, when I visited his laboratory. “There is genetic conflict everywhere. You see it in processes that you would never suspect; in cell division, for instance, and in the production of proteins involved in the very essence of maintaining life.
“One party is winning and the other losing all the time,” Malik went on. “That’s evolution. It’s the world’s definitive game of cat and mouse. Viruses evolve, the host adapts, proteins change, viruses evade them. It never ends.” The AIDS virus, for example, has one gene, called “vif,” that does nothing but block a protein whose sole job is to stop the virus from making copies of itself. It simply takes that protein into the cellular equivalent of a trash can; if not for that gene, H.I.V. might have been a trivial disease. “To even think about the many million-year processes that caused that sort of evolution,” Malik said, shaking his head in wonder. “It’s dazzling.”
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In order to understand retroviruses so we can combat them, we have to mess around with them: recreate them, try and change their DNA. The unfortunate downside, of course, is that as this becomes easier to do, it becomes a more appealing biological weapon for terrorists and rogue states.
I have always maintained that continued scientific investigation always outweighs the possible consequences, but this line of research is treading very close to "dangerous science."
The article also discusses how one researcher managed to bioengineer the polio virus, just to "prove that it could be done." Now that, in my opinion, is just plain fucked up.
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