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The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
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Source: http://www.sciencemag.org/content/336/6081/539.full
Science 4 May 2012:
Vol. 336 no. 6081 p. 539
DOI: 10.1126/science.336.6081.539
American Association of Physical Anthropologists
Older fathers often get blamed for passing on genetic mutations to their children, causing some types of autism, schizophrenia, and other disorders. But new data presented at the meeting suggest that children of older fathers and grandfathers may inherit at least one advantage from aging patriarchs: longer telomeres, structures at the tips of chromosomes that may protect against aging and disease. And the effect is amplified over the generations: “We've shown that the paternal grandfather's age is associated with longer telomeres in his grandchildren,” graduate student Dan Eisenberg of Northwestern University in Evanston, Illinois, reported in a talk. Telomeres are repetitive sequences of DNA that prevent the ends of chromosomes from unraveling, much like the plastic tips on the ends of shoelaces. As cells divide and replicate, telomeres get shorter and eventually can no longer prevent the fraying of DNA and the decay of aging. Recent studies have found a link between living to 100 and having a hyperactive version of telomerase, an enzyme that keeps telomeres long.
for those who are not afraid of the future : http://www.rael.org
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Source: http://www.sciencemag.org/content/336/6081/539.full
Science 4 May 2012:
Vol. 336 no. 6081 p. 539
DOI: 10.1126/science.336.6081.539
American Association of Physical Anthropologists
Older Dads Have Healthier Kids Than You Think
New data presented at the meeting suggest that children of older fathers and grandfathers may inherit longer telomeres, structures at the tips of chromosomes that may protect against aging and disease.
Telomeres in sperm cells, however, are exceptional: Several studies have shown that they grow longer, not shorter, over the years, probably because telomerase activity is high in testes. As a result, sperm cells from older men have longer telomeres than those of younger men. That would suggest that the older a father is at conception, the longer the telomeres his sons and daughters inherit.
Working with Northwestern biological anthropologist Christopher Kuzawa and anthropological geneticist Geoff Hayes, Eisenberg examined data from a long-term study of 3327 women who were pregnant in 1983 in the Cebu Longitudinal Health and Nutrition Survey in the Philippines. They had gathered the ages of fathers and in 2005 measured telomere length in the blood of 1845 moms and 1681 children.
Children of older fathers did indeed have longer telomeres than those of younger dads: For each additional decade of age in fathers at conception, sons and daughters had 4% longer telomeres, a finding that corroborates earlier work. The Northwestern group also found that for every additional decade of age in grand fathers, the grandchildren's telomeres added another 4%. But grand fathers did not pass on their longer telomeres to their daughters' children, only their sons', suggesting that this is a paternal effect.
The increase in telomere length per year of fathers' age is just about the same amount as telomere length lost per year in normal aging, Eisenberg says. So the longer telomeres in sperm roughly offset normal aging, giving children of older dads an advantage. “It's as if you delay reproduction, you earn this kind of higher fitness for your offspring,” says biological anthropologist Koji Lum of Binghamton University in New York.
Any benefit in telomere length may still be swamped out by the risk of passing on more mutations, Eisenberg warns: “We don't know yet the net health effect.” So at the moment, he's not advising anyone to delay fatherhood.
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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