Saturday, September 08, 2012

Re-engineering Human DNA?

Sounds like someone wants to:

Breakthrough Changes Thinking About DNA
Sept. 7, 2012 -- In what scientists call the biggest breakthrough in genetics since the unraveling of the human genome, a massive research effort now shows how the genome works.

The human genome contains 3 billion letters of code containing a person’s complete genetic makeup.

The biggest surprise is that most of the DNA in the genome -- which had been called "junk DNA" because it didn't seem to do anything -- turns out to play a crucial role. While only 2% of the genome encodes actual genes, at least 80% of the genome contains millions of "switches" that not only turn genes on and off, but also tell them what to do and when to do it.

Eleven years ago, the Human Genome Project discovered the blueprint carried by every cell in the body. The new ENCODE project now has opened the toolbox each cell uses to follow its individual part of the blueprint. The effort is the work of more than 400 researchers who performed more than 1,600 experiments.

The genome, with its 3-billion-letter code, reads from beginning to end like a book. But in real life, the genome isn't read like a book. The ENCODE data shows it's an intricate dance, with each step carefully choreographed.  [...]
OK, that's all very interesting. It's a fascinating article. But this jumped out at me:
[...] Eric D. Green, MD, PhD, director of the NIH's National Human Genome Research Institute (NHGRI), notes that most known disease-causing DNA mutations are in the small part of the genome that encodes genes.

"Most of these known mutations cause rare diseases," Green said. "But for the great majority of diseases, it's changes in the switches themselves. Diseases that are more common probably involve multiple DNA variants outside the genes. Common diseases like hypertension, heart disease, and diabetes are probably caused by things sitting in these switches." [...]
No. The "switches" don't cause the disease. The causes are things like bad diet and lack of exercise, etc, conditions which in turn cause the body to have a natural response by triggering things in the switches.

The disease is a warning that we are doing something wrong. Dr. Green seems to be implying that if we can turn off the triggers in the switches, we can stop the disease. But if we do that, you can be sure that the imbalance that would have triggered the disease, will then manifest somewhere else, some other way, in perhaps even a worse form.

Duh! I don't need a PhD to see that.

It's an area of study that we will inevitably pursue, but how that knowledge is used should be approached very conservatively. Nature does things for a reason. Altering that should not be approached lightly. Anyway, it IS an interesting read.    

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