Recently, it has been shown that germ-cells, too, are subject to epigenetic change, sometimes in response to environmental stimuli.

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But the cells from the first divisions retain the ability to form entire new embryos themselves. (This is how identical twins form.) Germ-line manipulation would require taking some of these early-embryonic cells apart in order to discover what the genetic lottery had delivered to them (a process that would destroy the cells in question).

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Very soon after dendritic cells encounter germs via their TLR the process of acquiring pieces of the germ is actually increased before it is switched off by the time the dendritic cell reaches a lymph node, he said.

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