In “Brain gene activity changes through life” (Science News, October 28th, 2011), Laura Sanders reports,
“Essentially, we carry the same genes as mice,” he says. “However, in us, these genes are up to something quite different.”
Kleinman and his colleagues turned up a curious finding: Many of the genes that slow down right after birth show a surge of activity as a person gets older. “The biggest changes that are going on occur fetally,” he says. “And then they drop off until mid-life, and then in the 50s to 70s, expression changes pick up again and become quite dramatic.”
Researchers don’t yet know what to make of this reversal, says Colantuoni. “We have just scratched the surface of what it means.”
Actually, if we assume that a natural human life span is about 70 to 80 years of age – a millennial assumption* – it would be a logical design feature. Aging requires considerable adaptation and accommodation to a situation where experience increases while physical strength declines. Maybe genetic changes help.
“The complexity is mind-numbing,” says neuroscientist Stephen Ginsberg of the Nathan Kline Institute and New York University Langone Medical Center, who wasn’t involved in the studies. “It puts the brain in rarefied air.”
* Interesting that the 70-80 year lifespan has been an assumption during millennia when most people cannot have lived that long. Does anyone think that “The prayer of Moses, the Man of God” (3 millennia old?):
The length of our days is seventy years-or eighty, if we have the strength; yet their span is but trouble and sorrow, for they quickly pass, and we fly away. v10
was written during a period when most people did live that long? They must have seen a pattern that made sense, even if it was not often completed.