Chromosome challenge

[dgevert]

Comparison of the Human and Great Ape Chromosomes as Evidence for Common Ancestry

Chromosome Challenge Discussion

Posted by scigirl on another forum

Long long ago, in a lab far far away, scientists figured out that chimpanzees have 24 chromosomes in their sperms and eggs, whereas humans only have 23. Therefore, these great scientists theorized that two of our chromosomes had fused together sometime in the recent past (aka million years ago.). Their theory made 3 predictions:

1) One of our chromosomes would look like two of the chimp chromosomes stuck together.
2) This same chromosome would have an extra sequence in it that looked like a centromere. Centromeres are the things in the middle that microtubules grab onto to divide a pair of chromosomes during mitosis.
3) It would also have telomeres (ends) but in the middle - and they would be in reverse order. Sort of like this:

ENDchromosomestuffDNEENDchromosomestuffDNE

See the "DNEEND" in the middle? That's what two telomeres would look like if two chromosomes were stuck together.

Lo and behold, these theories were put to the test. To test prediction 1, know that chromosomes all have a unique banding patttern. A "fingerprint." To test 2 and 3, you need sequence data. Telomeres and centromeres have characteristic DNA sequences.

What did those scientists find:

http://www.gate.net/~rwms/hum_ape_chrom_2.gif

H=human, C=chimp, G=George Bush I mean Gorilla**, O=orangutan.

and

Quote:
The second prediction - remnants of the 2p and 2q centromeres is documented in reference 4. The normal centromere found on human chromosome 2 lines up with the 2p chimp chromosome, and the remnants of the 2q chromosome is found at the expected location based upon the banding pattern.


and

Quote:
Telomeres in humans have been shown to consist of head to tail repeats of the bases 5'TTAGGG running toward the end of the chromosome. Furthermore, there is a characteristic pattern of the base pairs in what is called the pre-telomeric region, the region just before the telomere. When the vicinity of chromosome 2 where the fusion is expected to occur (based on comparison to chimp chromosomes 2p and 2q) is examined, we see first sequences that are characteristic of the pre-telomeric region, then a section of telomeric sequences, and then another section of pre-telomeric sequences. Furthermore, in the telomeric section, it is observed that there is a point where instead of being arranged head to tail, the telomeric repeats suddenly reverse direction - becoming (CCCTAA)3' instead of 5'(TTAGGG), and the second pre-telomeric section is also the reverse of the first telomeric section. This pattern is precisely as predicted by a telomere to telomere fusion of the chimpanzee (ancestor) 2p and 2q chromosomes, and in precisely the expected location.

I've never seen a creationist respond to this challenge. I've personally posted it on several forums in several discussions, and I've seen it posed by others many times too. Those of you who think evolution has no supporting evidence: what's your explanation, eh?

 

[quakefiend420]

very interesting...i think any creationist with half a brain is going to avoid this discussion like the plague...

 

[JustAnAverageGuy]

Interesting indeed.

 

[TuxDave]

:thumbsup:

 

[aceofspades230]

Creationists would not have a problem at all refuting your argument...according to their logic. However from a scientific viewpoint it is much harder to both prove the evolution and disprove it. Hate to say it but this evidence would not help your argument that much. First of all you should know exactly what you quoted and im not sure you do... It simply states that pieces chimp DNA looks similar to an unbroken stand, which is great for all of those scientists who are researching human evolution but to a creationist mentality, it means that DNA polymerase (a protein agent) suddenly broke off the copying of strand. I am not sure why you quoted

Quote:
Telomeres in humans have been shown to consist of head to tail repeats of the bases 5'TTAGGG running toward the end of the chromosome. Furthermore, there is a characteristic pattern of the base pairs in what is called the pre-telomeric region, the region just before the telomere. When the vicinity of chromosome 2 where the fusion is expected to occur (based on comparison to chimp chromosomes 2p and 2q) is examined, we see first sequences that are characteristic of the pre-telomeric region, then a section of telomeric sequences, and then another section of pre-telomeric sequences. Furthermore, in the telomeric section, it is observed that there is a point where instead of being arranged head to tail, the telomeric repeats suddenly reverse direction - becoming (CCCTAA)3' instead of 5'(TTAGGG), and the second pre-telomeric section is also the reverse of the first telomeric section. This pattern is precisely as predicted by a telomere to telomere fusion of the chimpanzee (ancestor) 2p and 2q chromosomes, and in precisely the expected location.

A chromotid (spelling?) was spliced, and reformed with its sister to recreate a new pair
But what does that mean for the purpose of the your argument???

It means that for some reason, DNA polymerase transcribing the DNA for meiosis (i wish i could give you a website for more details on that) was suddenly ordered by a cascade of chmicals to stop the chain and make a cut in the strand. It could of been a random error or a change to environmental stimuli, but the fact is that over a short period of evolutionary time a sweeping change of the DNA pool created the first human ancestors from the chimp ancestor. Why??? Thats a great question that still goes unanwsered, and one of the researchers goals might have been to try and anwser this question better.


What more could a creationist ask for in this day and age than a large change without a sufficent explaination?? This is an example why intellegent design is thriving...

I'm just trying to level the playing field for anyone who wants the the truth. Most creationists have ignored much more persuave evidence against straight creationism and there is no reason why they wouldn't ignore this. Supporters of intellegent design get a small foothold on the uncertainties of scientists, but they would just as surely be crushed under the other evidence of evolution, like the nature of mitocondrial DNA.

BTW I am a stout evolutionist and agnostic/atheist (if you couldnt tell that) but its important to treat those who don't believe like us fairly and avoid insulting them (without reason).

 

[Gibsons]

I've used a near identical argument in debates with creationist/ID types. I'm not sure they understood me (I didn't have pictures), nor did they appreciate the fact that evolutionary theory has made testable predictions which proved to be correct.

Instead, I got back links to sites like this (warning! this site will make you want to claw your eyes out).

 

[unipidity]

The proximal cause of change, you mean? Because its not as though we are ever going to come up with a reason for that, are we? Its the very nature of mutation- apparently and at some level actually random.

 

[RotoSequence]

Well, let me be the first to make a counter argument.

Assuming that this genetic "crossing" is plausible to occur in nature, we have to think about this. Why do we not hear about gorillas or monkeys giving birth to human beings, or vice-versa? In a species as promiscuous as humanity, where at least eleven billion people have been known to exist, it would seem that such events or at least ones to similar degrees would have occured; however, they have not. Another point that needs to be considered is the outcome of known cases of genetic mutation, such as the extra chromasome that causes downs syndrome. Or perhaps skin cancer. Both of these are caused by events that are touted to create the genetic mutation that makes evolution plausible, like the sun's rays and radiation. Theoretically with our thinning ozone layer we should be seeing more "evolutionary changes" in the species across the planet. However, what we are seeing, other than climate changes, are increased cases of skin cancer induced by ultraviolate rays. All mutation that we do see is harmful to the organism within which it occurs. I cant recall off the top of my head, nor do I have the time to google for it, but there was also a discovery that there is a genetic cap within creatures that prevents further genetic adaptations. I could continue, but for now, I need to disconnect. (stupid dialup )

 

[dgevert]

Originally posted by: RotoSequence
Well, let me be the first to make a counter argument.

Assuming that this genetic "crossing" is plausible to occur in nature, we have to think about this. Why do we not hear about gorillas or monkeys giving birth to human beings, or vice-versa? In a species as promiscuous as humanity, where at least eleven billion people have been known to exist, it would seem that such events or at least ones to similar degrees would have occured; however, they have not. Another point that needs to be considered is the outcome of known cases of genetic mutation, such as the extra chromasome that causes downs syndrome. Or perhaps skin cancer. Both of these are caused by events that are touted to create the genetic mutation that makes evolution plausible, like the sun's rays and radiation. Theoretically with our thinning ozone layer we should be seeing more "evolutionary changes" in the species across the planet. However, what we are seeing, other than climate changes, are increased cases of skin cancer induced by ultraviolate rays. All mutation that we do see is harmful to the organism within which it occurs. I cant recall off the top of my head, nor do I have the time to google for it, but there was also a discovery that there is a genetic cap within creatures that prevents further genetic adaptations. I could continue, but for now, I need to disconnect. (stupid dialup )

Are you serious? We don't see cross-breeding between gorillas or monkeys and humans because we are different species and we are not compatible with them.

The claim that genetic mutations are always negative is a myth. Take, for example, sickle cell. But wait, you say, isn't that a disease? Yes...however, in Africa, having sickle cell is actually a positive trait - it provides resistance to malaria. In general, traits are neither positive or negative overall - it depends on the environment around the organism as well.

If yu're going to claim that there was a discovery of a genetic cap, that's quite an assertion. I can't take that on faith, certainly not from someone who tried to claim that gorillas and humans not cross-breeding is evidence against evolution.

 

[dgevert]

Originally posted by: aceofspades230
Creationists would not have a problem at all refuting your argument...according to their logic. However from a scientific viewpoint it is much harder to both prove the evolution and disprove it. Hate to say it but this evidence would not help your argument that much. First of all you should know exactly what you quoted and im not sure you do... It simply states that pieces chimp DNA looks similar to an unbroken stand, which is great for all of those scientists who are researching human evolution but to a creationist mentality, it means that DNA polymerase (a protein agent) suddenly broke off the copying of strand. I am not sure why you quoted

Creationists don't *have* logic. I'm not sure what you mean when you say "to a creationist mentality..."

A chromotid (spelling?) was spliced, and reformed with its sister to recreate a new pair
But what does that mean for the purpose of the your argument???

It means that it's quite interesting to see such uncanny similiarities between two species who we have long thought to share common genetic ancestry. From a design standpoint, there's no particular reason a designer would design humans to just happen to look like one of their chromosomes is a merged version of two chromosomes in humanity's genetic cousins.

It means that for some reason, DNA polymerase transcribing the DNA for meiosis (i wish i could give you a website for more details on that) was suddenly ordered by a cascade of chmicals to stop the chain and make a cut in the strand. It could of been a random error or a change to environmental stimuli, but the fact is that over a short period of evolutionary time a sweeping change of the DNA pool created the first human ancestors from the chimp ancestor. Why??? Thats a great question that still goes unanwsered, and one of the researchers goals might have been to try and anwser this question better.

Right, and this change was inherited as humanity evolved.

What more could a creationist ask for in this day and age than a large change without a sufficent explaination?? This is an example why intellegent design is thriving...

The explanation is quite sound. Intelligent design is thriving as a political movement, not a scientific one.

I'm just trying to level the playing field for anyone who wants the the truth. Most creationists have ignored much more persuave evidence against straight creationism and there is no reason why they wouldn't ignore this.

I agree. Creationists have a long history of ignoring any evidence that doesn't fit their worldview.

Supporters of intellegent design get a small foothold on the uncertainties of scientists, but they would just as surely be crushed under the other evidence of evolution, like the nature of mitocondrial DNA.

They only get a small foothold among those ignorant of evolutionary science. It's quite telling that one of the most well-known IDers - Michael Behe - still accepts common descent as a fact.

BTW I am a stout evolutionist and agnostic/atheist (if you couldnt tell that) but its important to treat those who don't believe like us fairly and avoid insulting them (without reason).

Are you? Your signature makes me doubt that. And to respond to that, I don't think ceasing to exist is a worse alternative to eternal torture...

I apologize for the time it took me to reply. I spent several hours today in the hospital as a result of horribly bad abdominal pain and cramping that showed no sign of easing up or going away after nearly a day.

 

[dgevert]

http://webpages.charter.net/rufusatticus/YunisFig2.GIF

What's interesting here is that, if one takes into account the fact that the great majority of DNA is "junk DNA" and serves no purpose from a design standpoint, it's interesting to see such incredible similiarities between our DNA and that of our distant cousin (according to evolution), the chimpanzee. From a design standpoint, there's no logical reason an omniscient, omnipotent designer would go to such lengths to ensure that we see such similiarity in genetic code that doesn't do anything.

 

[RotoSequence]

Cross breeding was not the concept at work; I dont know where you derived that from, but I was stating that humans breeding with humans hasnt resulted in something non-human, nor has gorillas breeding with gorillas resulted in something non-gorilla in all that we have seen with solid irrefutable proof.


:edit: Although it is kind of ironic that you speak of people and monkeys not breeding thanks to genetic inompatability, whilst simultaneously claiming basis for common descent using the argument of similar DNA

 

[dgevert]

Originally posted by: RotoSequence
Cross breeding was not the concept at work; I dont know where you derived that from, but I was stating that humans breeding with humans hasnt resulted in something non-human, nor has gorillas breeding with gorillas resulted in something non-gorilla in all that we have seen with solid irrefutable proof.

Species evolving into other species is not something that can be witnessed overnight. You betray a severe lack of understanding of evolutionary theory with your post here.

:edit: Although it is kind of ironic that you speak of people and monkeys not breeding thanks to genetic inompatability, whilst simultaneously claiming basis for common descent using the argument of similar DNA

An ISA expansion card and a PCI expansion card are a lot alike in how they connect to a motherboard, but does that mean that you can put an ISA card in a PCI slot? No.

 

[Anubis08]

Actually I am a creationist and we discussed this in genetics class last semester. We cam eto the conlusion that this was at best shaky. One, you would need two centromeres for this to work on the same chromosome. Second, the odds of any animal surviving with this alteration is slim. Ever heard of Down's syndrome. There are actually 3 different ways to get it. Trisomy 21, nondisjunction, and chimera. This is similar to nondisjunction. Plus you would have to have the mutation of losing the extra chromosome if mating occurred between hybrid and ape in early days. Then you would have to somehow get a male and female with both sets of the same mutation to breed humans. If a computer program is perfect and you could build something else by slightly modifying it, would you write a whole new code if you also wrote the first . I think not, and I doubt God would either.

 

[Gibsons]

Second, the odds of any animal surviving with this alteration is slim

You're guessing.

Ever heard of Down's syndrome. There are actually 3 different ways to get it. Trisomy 21, nondisjunction, and chimera. This is similar to nondisjunction.

The problem with this kind of analysis is...

Back in WWII (or some war), they did a survey of where aiplanes got shot. They had someone record bullet strikes on the airplanes and catalog them. Idea was just to see if there were spots more prone to get hit, and adjust aiplane design accordingly by armor or moving vital parts away, etc. What they realized was that they were only recording hits that planes could fly back with. They saw a lot of hits on the tails wingtips etc... but hardly any though the cockpit.

We're in the reverse situation with genetics. We find out about chromosome translocations when they cause cancer or some other disease. Chances are, there are many many translocations that occur (somatically) and have no phenotype. There are examples of overtly normal humans with translocations. They aren't found very often because overtly normal people rarely, if ever, have a full cytogenetics spread done. But if someone has a leukemia or lymphoma, chances are they'll do a spread.

If a computer program is perfect and you could build something else by slightly modifying it, would you write a whole new code if you also wrote the first . I think not, and I doubt God would either.

Perfect? LOL. If god wrote out our genome, please have him PM me, I wanna ask why he screwed up so much.

 

[aceofspades230]

Dgevert im glad you responded so thoroughly to my post.

Lets get the personal and inconsequential stuff out of the way first. I think that losing everything, your thoughts, ideas, feelings, experiences, emotions, and literally everything else that makes up life is the worst possible outcome, but i would have to imagine that suffering some kind of eternal torment isn't high on the list of fun things either. I don't pretend to know anything about the transition of life to death and id really not rather find out.

The problem with the sudden gene pool change being random is that it's well random... Randomness of course means that there was a probability that humans could have never evolved and many people are unhappy with that fact. I don't think anyone likes being a lucky outcome of a chance game played before the human race had existed. I believe that the adaptation of tools and skills by some monkeys (normal varience) fueled the evolution. In current poplutions of organisms, rapidly changing stimuli and and inter-species competition respectively, are the #1 and #2 forces that act on a gene pool.

One further note on junk DNA... It's not all junk DNA
Apparently the information density required to create all the proteins neccessary is larger than the amount contained in so called "non junk" DNA. Biologists are looking deeper for organization patterns in both junk and active DNA. noting that it would be possible for more than code to be stored in the same strech. Not to say that theres no such thing as junk dna, there's still more "worthless" dna than possibly coded ones. If I need to I'll roll out the new college textbooks to look further into this subject.

Sorry to hear about the stomach pains, they really suk.

 

[glugglug]

Originally posted by: RotoSequence
Well, let me be the first to make a counter argument.

Assuming that this genetic "crossing" is plausible to occur in nature, we have to think about this. Why do we not hear about gorillas or monkeys giving birth to human beings, or vice-versa?

Ever read the Weekly World News?

 

[Gibsons]

Apparently the information density required to create all the proteins neccessary is larger than the amount contained in so called "non junk" DNA.

have a cite for this?

 

[DrPizza]

I just caught a portion of something about "junk DNA" a couple weeks ago... either on the television or NPR or something... apparently, geneticists were wrong to refer to it as "junk" - according to the speaker, it's rather important for some reason or other... I didn't catch the whole thing though.

 

[berkut7]

I was thinking about reading this, but skimmed first and stopped here "H=human, C=chimp, G=George Bush I mean Gorilla**, O=orangutan. "

Now I know reading this would be a waste of my time. Good job, and thanks for saving me some time.

 

[Malak]

Originally posted by: dgevert
I've never seen a creationist respond to this challenge. I've personally posted it on several forums in several discussions, and I've seen it posed by others many times too. Those of you who think evolution has no supporting evidence: what's your explanation, eh?

Why are you asking for a creationist response? We have our own very convincing evidence for our belief, which can explain anything away. None of that matters thought. You still have to convince the greater science community before I would even care. Macro evolution is still alternative and often ridiculed.

 

[dgevert]

Originally posted by: malak

Originally posted by: dgevert
I've never seen a creationist respond to this challenge. I've personally posted it on several forums in several discussions, and I've seen it posed by others many times too. Those of you who think evolution has no supporting evidence: what's your explanation, eh?

Why are you asking for a creationist response? We have our own very convincing evidence for our belief, which can explain anything away. None of that matters thought. You still have to convince the greater science community before I would even care. Macro evolution is still alternative and often ridiculed.

The scientific community has accepted macroevolution for about oh, a hundred years now. It is not "still alternative" and it is not "often ridiculed."

A book written thousands of years ago does not count as evidence, sorry.

 

[dgevert]

Originally posted by: DrPizza
I just caught a portion of something about "junk DNA" a couple weeks ago... either on the television or NPR or something... apparently, geneticists were wrong to refer to it as "junk" - according to the speaker, it's rather important for some reason or other... I didn't catch the whole thing though.

It provides some degree of protection against DNA degradation. However, there's still no reason to assume that it would be very similiar among species we already thought were related, from a design perspective.

 

[dgevert]

Originally posted by: berkut7
I was thinking about reading this, but skimmed first and stopped here "H=human, C=chimp, G=George Bush I mean Gorilla**, O=orangutan. "

Now I know reading this would be a waste of my time. Good job, and thanks for saving me some time.

So you're just going to ignore scientific evidence simply because of a tongue-in-cheek joke that I didn't even write? Nice.

 

[dgevert]

Originally posted by: aceofspades230
Dgevert im glad you responded so thoroughly to my post.

Lets get the personal and inconsequential stuff out of the way first. I think that losing everything, your thoughts, ideas, feelings, experiences, emotions, and literally everything else that makes up life is the worst possible outcome, but i would have to imagine that suffering some kind of eternal torment isn't high on the list of fun things either. I don't pretend to know anything about the transition of life to death and id really not rather find out.

Well, I obviously disagree. Either way, I prefer to believe in what makes the most logical sense, with the most evidence, regardless of whether it makes me feel good or not.

The problem with the sudden gene pool change being random is that it's well random... Randomness of course means that there was a probability that humans could have never evolved and many people are unhappy with that fact. I don't think anyone likes being a lucky outcome of a chance game played before the human race had existed. I believe that the adaptation of tools and skills by some monkeys (normal varience) fueled the evolution. In current poplutions of organisms, rapidly changing stimuli and and inter-species competition respectively, are the #1 and #2 forces that act on a gene pool.

Mutations = random. Natural selection = the very opposite of random. Therefore, evolution = not random.

One further note on junk DNA... It's not all junk DNA
Apparently the information density required to create all the proteins neccessary is larger than the amount contained in so called "non junk" DNA. Biologists are looking deeper for organization patterns in both junk and active DNA. noting that it would be possible for more than code to be stored in the same strech. Not to say that theres no such thing as junk dna, there's still more "worthless" dna than possibly coded ones. If I need to I'll roll out the new college textbooks to look further into this subject.

Your use of the word "information" makes me suspicious. I've only ever seen IDists use the word "information," and always without providing a meaningful definition for the word.

Sorry to hear about the stomach pains, they really suk.

Yes, they do. Still experiencing them too. I suspect a mild case of food poisoning (I only say mild because I haven't been puking everywhere)