Yesterdays fringe science has a way of becoming today's mainstream scientific gospel.
Only a few short years ago, the idea that our environment could change our genetics during our lifetimes seemed absurd. There were a few fringe medicine practitioners that believed otherwise. Now a new field of science being termed epigenetics has proven those fringe practitioners correct and promises to open up an entirely new field of medicine providing treatments for many currently untreatable conditions.
Epigenetics changes our genetic makeup not by changing the molecular codes of our DNA, but by either enhancing or suppressing the expression of various genes.
A methyl group can attach itself to a segment of DNA preventing transcription enzymes from transcribing that segment into messenger RNA that can then direct protein synthesis. Alternately, a hydroxyl group can attach in such a way that it pushes the DNA strands outwards increasing their expression. These modifications begin at conception and accumulate throughout life. What's more, specific external conditions can result in the enhancement or suppression of specific genes. In short, or genome contains conditional code just like a computer program. If condition then do ... is part of our genetic machinery enabling us to effectively adapt our genome to environmental conditions.
Recently, the entire genome of a number of pairs of identical twins was sequenced and compared letter for letter. It used to be that it was commonly believed that a significant cause of aging was genetic damage due to oxidative stress. While individual cells may indeed incur genetic damage, overall our genome is rather well preserved with age. Two identical twins 65 years of age, one developed cancer, one didn't. Their DNA was sequenced and compared. Not a single coden was changed, their entire genome agreed letter-by-letter. What was different was the epigenetic data. In fact, it was almost entirely different.
The cause of the cancer was in fact not a genetic mutation, but an epigenetic change, the methylization of a tumor suppressive gene that in a normally functioning cell would have prevented the uncontrolled growth. They administered a drug known to remove methyl groups from DNA. The idea was return the tumor suppression gene to normal functioning. Instead of trying to kill cancer cells, they aimed at returning them to normal. As of the time the documentary I was watching was produced, the woman was in remission.
There was a set of younger twins, I think they said ten years old but I'm not sure. One was autistic the other was not. Again, DNA sequenced was identical, the only differences were in the epigenetics. They found that the autistic girl had much smaller hippocampus, a region of the brain involved in memory formation among other things. Identical DNA, same environment, the only thing that could explain the difference were these epigenetic differences.
Experiments with rats even showed that these changes could be passed on to offspring. Particularly, the effect of nurturing not only affected adults through epigenetic changes, but their offspring as well.
These ideas have been known to some alternative medicine practitioners for decades, but were dismissed as impossible by mainstream science, are now proven fact.
As we come to understand this new field better we may develop methods for precisely altering gene expression and by doing so we may find cures for many presently incurable diseases. The more open minded science is, the more we will benefit.
As long as we pretend we already know everything, real scientific progress is impossible.