Heritable epigenetic variation is however not Lamarkian, it is Darwinian inheriance. You still need to have variation that is selected, even if it is epigenetic.
For example you still cannot make a striped giraffe by stretching a zebra's neck as no cells from the zebra's neck will end up in the next generation. The cells that make sperm and eggs were all determined before you got your hands around the zebra's neck.
This result (the twins not the zebra) is not at all surprising to people in the genetics field and helps formalize well established concepts of incomplete penetrance of genetic traits and somatic (non reproductive tissue) mutation
The twin study did not look at reproductive tissues, but if the variation in epigenetics holds true there children of younger parents should be more like their parents
An important thing to remember is that plant genomes undergo frequent duplication of the entire genome. Many important crops (eg cereals) are polyploid and have at least four copies of everything in their genome. If a plant has been polypoid at some point in history, some of these genes may have moved around in the genome and explain how the extra copies got there. Normally these extra copies would be deleterious to the plant as they would be out of balance with other genes, and silencing of them would evolve. All that would be required is that the silencing be removed, and if the plant is going to die there is strong selection for this to happen. I agree with other poster who suggested this is likely to be epigenetic ( a change in the way the DNA is packaged, rather than the DNA itself) to explain the high frequency. However a similar finding in bacteria turned out to be a greatly increased mutation rate in the dying bacteria as the cell systems stopped working correctly. For those of you in unis or with access to Nature journals the link below summarizes the debate on the previous apparently lamarkian results in bacteria. http://www.nature.com/cgi-taf/DynaPage.taf?file=/n rg/journal/v2/n7/full/nrg0701_504a_fs.html&filetyp e=pdf
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This article from nature talks about some work from Emma Whitlaws group that sees heritable variation in coat colour of mice that are genetically identical. http://www.nature.com/ng/journal/v23/n3/full/ng11
http://www.mmb.usyd.edu.au/research.php?person=wh
Heritable epigenetic variation is however not Lamarkian, it is Darwinian inheriance. You still need to have variation that is selected, even if it is epigenetic.
For example you still cannot make a striped giraffe by stretching a zebra's neck as no cells from the zebra's neck will end up in the next generation. The cells that make sperm and eggs were all determined before you got your hands around the zebra's neck.
This result (the twins not the zebra) is not at all surprising to people in the genetics field and helps formalize well established concepts of incomplete penetrance of genetic traits and somatic (non reproductive tissue) mutation
The twin study did not look at reproductive tissues, but if the variation in epigenetics holds true there children of younger parents should be more like their parents
Had the convenient side effect of being able to nobble window emulation on the G5 as well.2 8
http://macslash.org/article.pl?sid=04/05/13/19542
An important thing to remember is that plant genomes undergo frequent duplication of the entire genome. Many important crops (eg cereals) are polyploid and have at least four copies of everything in their genome. If a plant has been polypoid at some point in history, some of these genes may have moved around in the genome and explain how the extra copies got there. Normally these extra copies would be deleterious to the plant as they would be out of balance with other genes, and silencing of them would evolve. All that would be required is that the silencing be removed, and if the plant is going to die there is strong selection for this to happen. I agree with other poster who suggested this is likely to be epigenetic ( a change in the way the DNA is packaged, rather than the DNA itself) to explain the high frequency. However a similar finding in bacteria turned out to be a greatly increased mutation rate in the dying bacteria as the cell systems stopped working correctly.n rg/journal/v2/n7/full/nrg0701_504a_fs.html&filetyp e=pdf
For those of you in unis or with access to Nature journals the link below summarizes the debate on the previous apparently lamarkian results in bacteria.
http://www.nature.com/cgi-taf/DynaPage.taf?file=/
There is a good book describing the Australian hacking scenes history. Download from:
http://www.underground-book.com/download.php3
`Underground' by Suelette Dreyfus
with research by Julian Assange
475 pages with bibliography
ISBN: 1 86330 595 5