Epigenetics

[Clodfobble]

I've been reading up on the latest advances in epigenetics for awhile now, because there is research implicating the concept in everyone's favorite dead-horse childhood disease. But it has implications for a huge number of diseases, including cancer, diabetes, Alzheimer's, and even aging itself. There's a very accessible article in Time this month on it:

We have had a long-standing deal with biology: whatever choices we make during our lives might ruin our short-term memory or make us fat or hasten death, but they won't change our genes — our actual DNA. Which meant that when we had kids of our own, the genetic slate would be wiped clean.

What's more, any such effects of nurture (environment) on a species' nature (genes) were not supposed to happen so quickly. Charles Darwin, whose On the Origin of Species celebrated its 150th anniversary in November, taught us that evolutionary changes take place over many generations and through millions of years of natural selection. But Bygren and other scientists have now amassed historical evidence suggesting that powerful environmental conditions (near death from starvation, for instance) can somehow leave an imprint on the genetic material in eggs and sperm. These genetic imprints can short-circuit evolution and pass along new traits in a single generation.

For instance, fruit flies exposed to a drug called geldanamycin show unusual outgrowths on their eyes that can last through at least 13 generations of offspring even though no change in DNA has occurred (and generations 2 through 13 were not directly exposed to the drug).