When, in 2001, the human genome was sequenced for the first time, we were confronted by several surprises. One was the sheer lack of genes: where we had anticipated by chance 100,000 in that location were actually as few as 20,000. A big surprise came from analysis of the genetic sequences, which revealed that these genes made up a mere 1.5 per cent of the genome. This is dwarfed by DNA etymologizing from viruses, which amounts to roughly 9 per cent.
On top of that, huge chunks of the genome be made up of mysterious virus-like entities called retrotransposons, pieces of selfish DNA that be to serve no function other than to make copies of themselves. These peak for no less than 34 per cent of our genome.
All in all, the virus-like components of the human genome amount to almost half of our DNA. This would once watch been dismissed as mere junk DNA, provided we now know that some of it plays a critical subprogram in our biology. As to the origins and function of the rest, we simply do not know.
The human genome therefore presents us with a paradox. How does this viral DNA come to be there? What role has it played in our evolution, and what is it doing to our physiology?
To answer these questions we need to deconstruct the origins of the human genome - a bosh more fantastic than anything we previously imagined, with viruses playing a bigger part than you might care to believe.
Around 15 days ago, when I was researching my book Virus X, I came to the conclusion there was more to viruses than meets the eye. Viruses are often associated with plagues - epidemics accompanied by dandy mortality, such as smallpox, flu and AIDS. I proposed that plague viruses excessively interact with their hosts in a more subtle way, through and through symbiosis, with important implications for the evolution of their hosts. Today we have growing establish that this is true (New Scientist, 30 August 2008, p 38), and overwhelming tell that viruses have...If you want to get a full essay, order it on our website: Ordercustompaper.com
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