On an evolutionary scale: if generation after generation found epigenetically-passed physiologies or behaviors useful, would such long-lasting methylations on histone proteins lead to permanent genes? Like genes for lactose tolerance or skin color? Did epigenetic molecular modications provide a fast-track for evolution, a process distinct from natural selection, and one much more responsive? Moshe and Michael talked with passion and ordered two more beers. The possibilities were staggering. Two scientists walked into a bar, and began a collaboration that launched the revolutionary science of “Epigenetics.”
What About that “Junk DNA”?
“For every complex problem there is an answer that is clear, simple, and wrong.” – H.L. Mencken
Since 1953, when Watson and Crick first unraveled its molecular structure, DNA has been considered the control tower of our biology, the stable double-helix that directed all the information that formed us, accurately and immutably from one generation to the next. Our DNA was acclaimed as our “destiny,” and the “master molecule” of life. With the discovery of the structure of DNA science had molecular proof of inheritance and breeding, destiny and disease.
But by the year 2000, however, even as the Human Genome Project had decoded all three billion base-pairs of DNA, and… and 21,000 of our genes, scientists still could not explain the genetic activity of 98% of our DNA! The enormous cost and effort of decyphering the “master molecule” of DNA had contributed nothing toward the understanding of 98% of its function. Perhaps the definition of “gene” needed re-thinking? Molecular biologists improvised, labeling this non-understood DNA as “non-coding DNA” – because it did not code for the production of proteins. Some went even further, claiming this “non-coding DNA” had accumulated from a billion years of evolutionary dead-ends, as so much hereditary and viral trash. This vast expanse of DNA devolved the nickname “Junk DNA,” as though evolution had used, then forgotten to throw away 98% of its genetic material.
By that time, however, evidence had already piled up… 1.) from a study of Swedish ancestors of famine victims in Överkalix, Sweden from 1836 onward that showed that under-nourishment at the time of conception puts succeeding generations at risk for eating disorders; 2.) from University of Maryland studies that show parental levels of exercise fitness and muscle development at the time of conception get passed on, and offspring develop muscle fitness accordingly; 3.) from England’s Avon Longitudinal Study of Parents and Children (ALSPAC) data which showed that the children and grand-children of habitual smokers suffer widespread health problems; 4.) from a study of famine victims of Wold War II; and, 5.) the ongoing work of Moshe Szyf and Michael Meany… implying that this 98% of our DNA could have important functions. Interdisciplinary science began re-thinking “Junk DNA.” Was the complex process of histone protein modification imprinting “acquired characteristics” that improved chances of survival along most of our DNA?