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How the world got lost on
the road to an anti-aging pill
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November 11, 2011: by Bill Sardi
Researchers are slow to concede that non-Darwinian models of aging may best explain human longevity.
In the Darwinian model an individual might have a genetic mutation inherited from their mother or father or both which is passed on to them. A gene mutation is defined as a substitution, deletion or insertion of an incorrect nucleotide on the DNA ladder. Adenine, guanine, cytosine and thymine represent the four nucleotide proteins that comprise the rungs on the DNA ladder. For example, a genetically similar group of short-statured people in Ecuador exhibit a gene mutation in a growth factor gene that confers unusual longevity upon them.
Contrary to static genes, epigenetics is the dynamic protein-making property of genes where genes produce (express) or negatively produce (silence) proteins. Alterations in genes that do not change the sequence of DNA nucleotides describe epigenetics.
Epigenetics was not known at the time of Darwin who postulated that observed changes in bird beaks over a two-month period of time served as evidence for the gradual development of new species. But what Darwin observed and then eloquently sketched in his field notebook could not have been the result of gene mutations but rather adaptation emanating from epigenetics.
Environmental factors such as food or lack of food, temperature or solar radiation can switch genes on or off.
What happens during conception and early development may epigenetically imprint genes which can be transferred on to following generations. Epigenetic imprinting may not last forever but it still has an inheritance.
Genetic imprinting has to do with the wrapping of bundles of genes called chromatic around what are called histone bodies, what would look like a double-coiled cable wrapped around a tennis ball. If the DNA coil (chromatin) is wrapped tightly around histone bodies than the genetic information is non transferable, much like a non-read file on your computer. If the DNA coil is loosely wrapped around histone then the genetic information can be accessed and epigenetic protein-making ensues.
In a groundbreaking experiment, researchers at Stanford University worked with roundworms that had mutations in one of three genes (ASH-2, WDR-5 and SET-2), genes which control how DNA is packaged or wrapped around histone bodies. By epigenetically altering the wrapping of chromatin around histones researchers were able to extend the lifespan of roundworms and then observe that epigenetic inheritance for longevity was passed on to succeeding generations. Genetically normal worms (no mutations) lived as long as long-lived grandparents who had mutations.
The red wine molecule resveratrol has been shown to be a dietary agent that helps to control epigenetic gene activity via its ability to alter chromatin wrapping around histones.
Bottom line, your biological inheritance does not doom you to a long or short life per se. There is even evidence that genes can be switched to produce longevity proteins among aged individuals. – © 2011 Bill Sardi, ResveratrolNews.com