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| quote: | Originally posted by RickyM
We're actually closer genetically to chimps, than chimps are to gorillas...and I think we're 98.6% genetically identical to a chimp |
Although newer studies have disproved this figure because they didn't take into account "insertions" (repetition of a corresponding sequence) and "deletions" (absence of a corresponding sequence) just single-base matchings. It seems that the actual difference is about 5%.
http://www.newscientist.com/article...ce-trebled.html
Still extremely small if one takes into account the substantial differences (e.g. behavioural, anatomical etc.) between the two species. As the article suggests, the difference would be in the "Regulatory" genes, not the genes per se. This would mean that a difference in frontal lobe size (being much larger in humans and hence accounting for some huge mental differences) would not be based on different genes (e.g. a seperate human gene coding for a larger frontal lobe) but in the same set of genes only regulated in different ways (e.g. the same gene that codes for frontal lobe size is the same in both humans and chimps, but in humans is not inhibited enough from another regulatory gene, staying more active and for a longer amount of time, leading to a larger size. This is an over-simplification ofcourse but you get the picture). This would mean that whilst the bases per se are very similar (in a matter of fact, 70% of our genes are similar to the bloody fruit-fly or something!), their dynamic expressions in space and time could lead to quite different protein interactions (the "interactome"-the mapping of protein interations- would be the next big-and possibly more substantial-milestone after the "genome").
This is why another study revealed that whilst the fruitfly has 14.000 genes and humans just 10.000 more (around 24.000 and with the majority of them being similar), the protein interactions of humans are 10 times more than the fruit-fly's (and this is actually a huge difference).
So, if one takes into account those "dynamic" aspects, the actual biological difference between humans and chimps could be much bigger. It seems that by just attributing the biological differences to the similarity of simple DNA bases is not enough.
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