Posted on 08/31/2005 6:18:11 PM PDT by neverdem
The first detailed genetic comparison between humans and chimpanzees shows that 96 per cent of the DNA sequence is identical in the two species. But there are significant differences, particularly in genes relating to sexual reproduction, brain development, immunity and the sense of smell.
An international scientific consortium publishes the genome of the chimpanzee, the animal most closely related to homo sapiens on Thursday in the journal Nature. It is the fourth mammal to have its full genome sequenced, after the mouse, rat and human being.
Some of the scientific analysis of the 3bn chemical "letters" of the chimp's genetic code focused on its remarkable closeness to the human genome. After 6m years of separate evolution, the differences between chimp and human are just 10 times greater than those between two unrelated people and 10 times less than those between rats and mice.
But most scientists are concentrating on the differences. The vast majority of these probably have little biological significance, said Simon Fisher of the Wellcome Trust Centre for Human Genetics at Oxford: "The big challenge for the future is to pinpoint the tiny subset of differences that account for the origins of unusual human traits, such as complex language."
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External website: Read Nature's interactive report on the chimp genome >Click here |
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The preliminary evidence suggests that the outstanding size and complexity of the human brain owes less to the evolution of new human genes than to the different way existing genes produce proteins as the human brain grows in the foetus and during infancy. Genes for transcription factors - molecules that regulate the activity of other genes and play a vital role in embryonic development - are evolving more quickly in humans than in chimps.
Three key genes involved in the human inflammatory response to disease are missing in chimps, which may explain some of the differences between the two immune systems. On the other hand humans have lost a gene for an enzyme that may protect other animals against Alzheimer's disease.
The clearest differences to emerge from the analysis are in the Y (male) sex chromosome. While the human Y chromosome has maintained its count of 27 active gene families over 6m years, some have mutated and become inactive on its chimp counterpart.
This finding contradicts the popular view that the human Y chromosome is withering away because it has no genetic "mate" with which to swap genes - a process that repairs damaged DNA on other chromosomes. Presumably an alternative repair mechanism has evolved in humans but not in chimps.
David Page of the Whitehead Institute for Biomedical Research suggested that mating habits in the two species might explain the difference. Because male and female chimps mate with multiple partners there is stronger selective pressure on sperm-producing genes and conversely less pressure on evolution to preserve other genes on the Y chromosome in the apes than in largely monogamous humans.
It's that 4% you gotta watch out for.
Some of us are more identical to chimps than others.
Must be because of "intelligent design'. Uhuh, yup.
I'd like to know where he found these largely monogamous humans of which he speaks.
Tomato and human DNA is 50% identical.
WHOOOPEEEDOOOO!!!!
Oranges and human beings share 75% of DNA .
Well, that settles it. I want to marry my chimp. We shouldn't be so specie-centric in our thinking. Afterall, they deserve every legal right you enjoy (carefully exempting self - a common tactic), And if they can't handle the full range of your rights, we'll just pare your rights back until they can. We must be egalitarian don't you know.
*Goes to the kitchen and makes some popcorn*
*Yells: Anyone want some?(
:)
Janet Reno's is 100%.
How about donkeys?
Which highlights the importance of the what and where of the differences.
On a more serious note, everyone seems so concerned with comparing an Oldsmobile to a Cadillac, without ever noticing the biggest difference: No one is driving the Oldsmobile. That, as they say, makes all the difference.
I wouldnt know not my area of expertise. But I would like to see comparison of grouper or sea bass DNA and human DNA and maybe rice DNA versus human DNA.
I read something pretty recently claiming theyd mapped rice DNA back on the 10th, (of August) I believe.
Moore or less 99%
Which part of the Donkey?
The other 4% is hiding out in the DU??
I'd say that's pretty intelligent design. Reuse what works.
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