Quote:
Originally Posted by kennyc
What I'm saying is that identical twins start with the same genome.
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Right, they *start* identical as a single cell.
Then a mutation in one cell, usually at the two or four cell stage causes the cell clusters to identify as "self" and "other" (yes, we are tribal down to the cellular level) and continue to develop independently with the variance (and others that accumulate) spread throughtout every cell of the resuting organism.
They *start* identical but once the variance emerges they develop and end up differently. The end-result genomes are different.
Don't want to go too far off-topic but recent full-genome studies are discovering that we are a very unstable species. So far nobody has found a Metagene or X-gene but what they are finding is that the "non-coding" regions are at least as important as the genes. The biggest surprise of the Human genome project was how small the gene count is given that were are such complex organisms; well, it turns out that the complexity starts out with how the information is stored and expressed.
The tradition 19th/20th century view of genes was akin to a pictographic writing system with each gene (symbol) representing one trait (or idea). The emerging picture is more of an alphabetic writing system where location and context changes the expression (meaning).
And that is about as far as I can take it heading back to the more familiar reading/writing territory. At least until we start using DNA to store encoded information for epub9 ebook readers.
(Whis is to say, I fully expect the dedicated reader category will persis. Doesn't mean eink will, though.)