Survival Of The Sickest Analysis

DNA and Genetics in Survival of the Sickest
, 2 Environmental Factors that Cause Mutations,
How Bacteria put under stress can be beneficial for evolution, And a Jumping Gene

In chapter 6 of “Survival of the Sickest” titled ‘Jump into the Gene Pool” Dr. Moalem jumps into exactly that. Starting us off with the origins of the Vaccine, which is quite interesting, and then, in a very humorous fashion, continues into DNA. Dr. Moalem explains to the reader that less than 3 percent of DNA contains instructions for building cells, which means that the other 97 percent of your DNA isn’t active in building anything. How does he make this humorous? Well, he explains, “If you took the DNA from any cell in your body` and laid it end to end,
it would reach the top of Shaquille O’Neal’s head-but the DNA that actively codes for building your body wouldn’t even reach his ankle”. But new research is starting to demonstrate that the massive volume of genetic information in this portion of our genome may play a critical role in evolution, because, that future that we imagine at the moment, where we live in harmony with bacteria and have adapted to sickness, is happening now, due to mutations.
2 environmental factors that are known to cause mutations are Radiation and the Sun. Outbreaks and pandemics are thought to be caused by antigenic drift, when a mutation occurs in the DNA of a virus. When the antigenetic drift in a virus is significant enough, our bodies don’t recognize it and have no antibodies to fight it-and that means trouble. What causes antigenic drift? Mutations, which can be caused by radiation. Which the sun spews in great amounts every eleven years. The potential for evolution begins when a mutation occurs during the reproductive process of a given organism. In most cases, that mutation will have a harmful effect or no effect at all, but sometimes, a random mutation will give it’s carrier an advantage, giving it a better chance to survive, and reproduce. That’s when natural selection comes in; the mutation will spread throughout the population and be passed down through generations and generations. Continued on Next
Page
Adaptations that truly benefit us will eventually spread across an entire species, like when the flu virus acquires the new characteristic to go pandemic. Barbara McClintock discovered what is commonly called the “jumping gene”, but it’s more proper (and less fun) of a name is transposons. McClintock believed that the jumps are a genomic response to internal or environmental stress that cells can’t handle under their existing setup. When under circumstances such as these, the organism must gamble on finding a mutation that could help it survive. When that happens, the proofreading mechanism is suppressed and mutations are allowed to blossom. Today scientists are following the steps of McClintock’s lead away from the notion that the genome is a rigid set of plans and that mutation-and in effect evolution- is only triggered by random errors. So as Dr. Moalem says “the genome likes to move the furniture around.”