The way some people picture and describe DNA reasearch reminds me of those cheesy old black and white monster movies (and some early film with color) where the "radiation" mutation scares were sometimes hilarious, without intending to be. People were running around and screaming about "radiation!" as if they were grade school children claiming to have been contaminated with "cooties" from some child of the other gender.
DNA research is amazingly complex. Let me invite the reader to this site: http://dnaresearch.oxfordjournals.org/. If you don't read the articles, try reading the titles with understanding. We are not talking about tests with chimps putting round pegs in round, as opposed to square, holes here.
The Pacific Northwest National Laboratory had a short but informative piece last year which described their search for "biomarkers" to help them address biological threats ranging from respiratory viruses to terrorist bioweapons: http://www.eurekalert.org/features/doe/2007-03/dnnl-bth032207.php. As they say, one of their target areas is this, "Biomolecular signatures, a set of genes, proteins, metabolites, and/or lipids, present a unique pattern of change in an organism that can be used to identify an exposure or response to a specific environmental stressor."
The chemical processes that go on in the biological world are astoundingly more complex than the world of Charles Darwin's day. While there will be the equivalent of frightened people running around screaming their fears of today's version of "cooties", over 'frankenfood' and genetic manipulation, someday, possibly quite soon, people will be clamoring for an injection with modified viruses. Modifications to the DNA of some viruses can and will carry the genetic codes to turn the tiny molecular switches that stop things ranging from acne to cancers. DNA research has already demonstrated that imbedded in the genetic code of every human being are genes which when switched on produce cancerous growths. Viral therapies are already in play to turn off those genetic code sequences in very much the same way that we upgrade our personal computers with "patches" to fix a particular flaw or prevent a problem.
That is what DNA is, a complex chemical program that makes us the physical persons that we are. Sometimes our problems are obvious and outside the range of DNA. Just today I did something that caused injury to my nose, that was the fault of my actions. Also today, as I have for many days in recent years, I looked at my thinning hair atop my head and wondered, "If only I could flip some genetic switch to use the DNA my mother contributed to grow hair atop my head-instead of the DNA my father contributed that caused me to grow a great head of hair for a while, and then lose it in my later years (or words to that effect). I have a friend who is a couple of decades older than me, but still has a beautiful head of hair atop his head. The difference between him and me? DNA. He has genetic codes that handle his testosterone differently than me. Mine gets modified to a form that is essentially toxic to the hair atop my head. His is not.
There are far more important things under study right now. Some cancers switch off some of the body's defenses against cancer, so they essentially protect their own deviant growth by using part of the body's code at the wrong time or in the wrong way for the benefit of the body. If someone were understanding of the DNA within us so that they could infect the body with a comparatively safe virus that injects the corrected code to change the status of the cancer from friendly tissue to problem tissue, then the body's defenses would be able to target those deviant cancer cells and remove them.
What a monsterously GOOD idea! Well, researchers by the hundreds are at work on these very things. Breakthroughs in DNA research are doing, and will soon be doing still far much more, good than harm.