Apes DNA v Human DNA.

Always Free

Critical Thinker
Always Free
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If apes have 96% the same DNA as humans what is the other 4% that makes us what we are?
 
Alfie,

Pretty damn important don't you think?

Actually I think that 96% figure includes junk DNA (non-functional DNA). Junk DNA comprises about 95% of the total but this figure may be way out because some of the junk DNA could turn out to have a function after all. If it's a true figure, however, and the difference (4%) between human and ape DNA is in the functional DNA only, then the difference is pretty substantial.

Hell, it better be!

regards,
BillyJoe
 
This might help

It is perhaps well to remember the size of the human genome of 3,200,000,000 base pairs......Although we may comprise of only 30,000 to 100,000 (high estimate) genes, each gene can comprise hundreds to thousands of base pairs, and it is the unique sequence of base pairs that makes up a gene. It can take only a few changes in the coding sequence of one gene to completely alter or inactivate the function of that gene
Click to expand...
 
BillyJoe said:
Alfie,

Pretty damn important don't you think?

Actually I think that 96% figure includes junk DNA (non-functional DNA). Junk DNA comprises about 95% of the total but this figure may be way out because some of the junk DNA could turn out to have a function after all. If it's a true figure, however, and the difference (4%) between human and ape DNA is in the functional DNA only, then the difference is pretty substantial.

Hell, it better be!

regards,
BillyJoe
Click to expand...

But why then do people, such as animal experts or scientists point out the 4% difference as if infering that there is only an actual 4% difference which I take it to mean very little difference?

I suppose I will have to look up this "junk DNA" as you describe it, myself.
 
Yeah, I think the 4% difference is across the board so that there is, in fact, a 4% difference in the functional DNA. The above link, which you probably missed before you posted, probably helps explain why such a small difference can make such a BIG difference. Goes to show too that evolution did not have much work to do to get from a chimpanzee to homo sapiens. ;)
 
BillyJoe said:
Yeah, I think the 4% difference is across the board so that there is, in fact, a 4% difference in the functional DNA. The above link, which you probably missed before you posted, probably helps explain why such a small difference can make such a BIG difference. Goes to show too that evolution did not have much work to do to get from a chimpanzee to homo sapiens. ;)
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Chimpanzees and Humans - Still Close Relatives Despite Wayward DNA
A new study compairing chimpanzee versus human DNA showed that genetic jumbling, unnoticed before, possibly explains why humans and our closest cousins seem so different when our basic DNA structure is so much alike. The rearrangement, addition and deletion in DNA could mean that certain genes are disabled. This process may play a bigger role in evolution that previously suspected. The formerly accepted and often quoted percentage of similarity of the human and chimp genomes was 98.5%. In light of this new comparison, this estimate seems too high, but still, the genomes are far more alike than they are different.

References:
http://www.pnas.org/cgi/content/abstract/99/21/13633

Thanks for that link Bill (I did miss it) I have put that into my favs to give it a good read later on.

I'm starting to understand why 4% can be a big difference;)
 
While the term "junk DNA" is used, it would probably be more appropriate to refer to it as "non-coding DNA". It does not code for protein sequences.
 
If so little difference separates us from chimpanzees, think how much less must be the difference between one human and another. (Or, like I did, look it up. I'm finding it quoted as less than .01%).

On average, two unrelated people differ at just one of every 1,000 sites in their DNA...

But these tiny variations add up to roughly 3 million places where two people
may differ, creating traits such as hair color, eye color or shade of skin.

...Tiny variations called single nucleotide polymorphisms (SNPs), the most
common type of variation in the genome, may underlie differences in traits
such as muscle composition, the body's response to exercise and metabolic
efficiency
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There is in fact less actual genetic difference between, say the shortest, blackest Pigmy and the tallest, blondest German, than we would expect (or so say some geneticists). It has been suggested (though it is still far from well-established) that the human population passed through a 'bottleneck' around 74k years ago--possibly the result of a 'volcanic winter'. I think Gould said that there is more variation in some groups of chimpanzees than there is in the entire human population worldwide.
 
People tend to get a bit carried away with the similarities between the human and primate genomes, IMO. It's important to remember that mammalian genomes are very highly preserved across species boundries. There are a lot of similarities between the human genome and those of cattle and mice. In the case of cattle (I work in the field of bovine genetics) the current estimate is that the bovine and human genome are 95% similar.

I've read that most of the differences between human and other primate genomes are in the regulatory sequences of genes, meaning that while the gene sequences are not that disimilar (if at all), they would be transcribed into mRNA at very different rates. RNA is also under post-trascriptional control, while amino acids translated from the mRNA sequence can also be under post-translational control. Nature published an article a few months ago detailing how a few base pair changes between in the same gene between humans and apes has allowed human jaw structure develop into a form capable of articulating speech.
 
I would just like to add that Gould mentions that it is thought that while it would seem that those genetical differences are minor,those few key genes that separate us do play a major role.
I´m using his earlier work as a reference,whether this is up to date or not I do not know of.
 
Something that has not been mentioned in this thread is that the ape genome (as far as I know) has not been sequenced yet!
(Not that there aren't people working on it)...

We don't know the precise differences between human and ape DNA (because we don't have a whole sequence)...the percent numbers are often derived by comparing small specific places (i.e. a specific gene) on the whole genome.

Th 98% similarity between cimpanzees and humans I think is gotten from cyctochrome c comparison (i.e. 98% of the DNA bases match up with the human gene...
 
The number I have heard is that we share 98.6% of our "active DNA" with chimps.

I have studied Chimpanzees in Gombe. They are amazingly similar to us. The things you notice are their fingernails, their eyes, and especially their ears, which are incredibly humanlike. :D
 
I don't remember who--I think it was Carl Sagan--but somebody once remarked, regarding stories of aliens mating with humans, that a human would stand a better chance mating with a geranium, since at least there there is some shared DNA, whereas the alien's DNA-equivalent would have had an entirely different evolutionary path.

So, does anyone here know what percentage of DNA we share with plants? with reptiles? amoeba?
 
human & chimp DNA

The amino acid sequences for human and chimpanzee cytochrome c are identical. You can retrieve the sequences at the NCBI site for comparison.

(http://www.ncbi.nlm.nih.gov/)

The original technique for comparing the DNA of two different organisms is to extract DNA from both, mix them together, melt them by heating the mixture (this separates the complementary strands from each other), then let them reanneal. The more similar the two genomes, the more heterogenous double helices (that is, DNA with one strand from one species and its complement from the other) form as the mixture cools. The more similar the strands, the more strongly they bond to one another. From the strength of this bonding, you can calculate the percent difference between the two sequences.

Now that we have DNA sequences for so many parts of human and chimpanzee genome (both coding and non-coding regions), we can make estimates of total differences by extrapolation from the differences in known sequences.
 
Re: human & chimp DNA

Kate said:
The amino acid sequences for human and chimpanzee cytochrome c are identical. You can retrieve the sequences at the NCBI site for comparison.

(http://www.ncbi.nlm.nih.gov/)

The original technique for comparing the DNA of two different organisms is to extract DNA from both, mix them together, melt them by heating the mixture (this separates the complementary strands from each other), then let them reanneal. The more similar the two genomes, the more heterogenous double helices (that is, DNA with one strand from one species and its complement from the other) form as the mixture cools. The more similar the strands, the more strongly they bond to one another. From the strength of this bonding, you can calculate the percent difference between the two sequences.

Now that we have DNA sequences for so many parts of human and chimpanzee genome (both coding and non-coding regions), we can make estimates of total differences by extrapolation from the differences in known sequences.
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Whether this is an improvement or not is arguable, given the recent findings about the importance of "pseudo-genes".
 
A little more on FOXP2:
www.wellcome.ac.uk/en/genome/genesandbody/hg05f004.html

www.cnn.com/2002/TECH/science/08/15/coolsc.speech/

A couple of changes in one gene about 200,000 years ago may be the reason apes still pound the ground -- and humans can recite poetry to communicate.
Click to expand...

They discovered a slight amino acid change in the human protein, which was not found in any of the other animals. That change may be a big reason humans developed the face and jaw structures, which make the profound capabilities of speech and language possible.
Click to expand...

There are not that many differences between the DNA of a human and a chimp, or even between a human and a whale. But, as knowledge of FOXP2 is revealing, even a tiny number of DNA mutations -- can lead to hugely important physical differences.
Click to expand...
 
Shane Costello--

"Nature published an article a few months ago detailing how a few base pair changes between in the same gene between humans and apes has allowed human jaw structure develop into a form capable of articulating speech."

How much of a role does the jaw play in speech though? The voice box and tongue are very necessary for speech but you can talk without moving your jaw.
 
Dymanic said:
I think Gould said that there is more variation in some groups of chimpanzees than there is in the entire human population worldwide.
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The way I remember it.....

"There is more variation within an ethnic group than between ethnic groups (of humans)"

But it could be an entirely different quote of course.
 
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