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Author Topic:   Introduction to Genetics
Taq
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Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


Message 211 of 233 (720094)
02-20-2014 10:41 AM
Reply to: Message 195 by Faith
02-19-2014 8:51 PM


Re: Factual versus interpretive tendentious terminology
It isn't artificial if it's true.

It is a human construct, so it is artificial.

But it IS an artificial position to take to pronounce it all normal alleles if it isn't -- again, an assumption, an article of faith.

You have a habit of ignoring evidence.


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Taq
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Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


(1)
Message 212 of 233 (720095)
02-20-2014 10:44 AM
Reply to: Message 202 by Faith
02-19-2014 11:40 PM


Re: Just some examples of assumptive mystification versus genuine science
THIS on the other hand is science mixed with pseudoscience:
http://en.wikipedia.org/wiki/Endogenous_viral_element
Most of it is science. The paragraph about paleovirology is where the pseudoscience comes in, where the data is crammed into the ToE's Old Earth assumption of millions of years for this or that. It purports to give the actual history of "germline integration events" as if it were possible to know anything about events in the genome millions of years ago.

It is possible because we find retroviruses in genomes. That is the evidence. No faith or pseudoscience needed. It is no different than finding a fingerprint at a crime scene.

This next one is the one Taq linked. Since it's about finding phylogenetic markers it's bound to get into the pseudoscience territory, and reading stuff like this is a horrific struggle for me, being a combo of unsupportable assumptions with genuine scientific facts, and of course some terminological struggles as well, but that part I'm not faulting:

And yet you can't point to any unsupported assumptions or pseudoscience. All you have is hot air.


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Taq
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Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


(2)
Message 213 of 233 (720096)
02-20-2014 10:46 AM
Reply to: Message 208 by Faith
02-20-2014 4:28 AM


Re: Paradigm clash
We can both repeat our complaints about our opponents' point of view, plus you've added the usual Science Creed and the Evo Creed, and it's all simply a statement of belief.

Hot air, again. We have shown you that it is a scientific theory backed by scientific evidence. Ignoring the evidence doesn't make it go away.

All you are doing here is a tit for tat, echoing exactly what I've been saying about evolutionism. Of course I suppose it can be said on both sides, but it IS true of evolutionism as I've been pointing out, that the interpretive sciences that support the ToE are wrapped around bald assumptions without any verification whatever.

And yet you can't show us a single bald assertion that is not backed up by evidence. Again, hot air.

•The ToE says All life was descended from earlier life. This is an article of faith, of belief, based on commitment to the ToE. It hasn't been shown to be true and it can't be shown to be true (is this a better way of saying it than "proved?) The particular Creationist model I've been pursuing says all life was created as separate Species in the same time frame as human beings. This IS a different model, wouldn't you say?

I just showed you the evidence demonstrating that humans and chimps share a common ancestor. ERV's are that evidence. All you did was run away from the evidence without ever engaging it.

•THe ToE says DNA evolved just as everything else did; YEC as I've been pursuing it says DNA was built in to the original Species or Kinds and the genome of each governs only that Species, and again, surely this must be considered to be an alternative model.
--- My particular defense of this idea is that the processes of evolution that isolate populations from each other, which is the general way races are formed, lead to reduced genetic diversity. This also appears to be the main route to "speciation" but if the supposed "new species" in fact has reduced genetic variability this is clearly a wishful fantasy. The YEC model as I understand it says that life was created to vary, to evolve over time, into myriads of fascinating new races, but that a calamity known as the Fall brought death into the world and now all life is threatened by disease and death whereas if the Fall had never happened we'd just have beautiful subspecies of every known Species. And again, this IS a model and it does have explanatory power. It's obvious that species are threatened by extinction. That's why we have conservationist programs.

That evidence is also found in ERV's. We can see ERV's diverge over time, both between species and between LTR's of the same ERV. It is all in the paper I gave you.

•The ToE says that mutations are the means by which DNA was/is created, while also admitting that most mutations are neutral and many are deleterious, claiming the latter are selected out. My YEC view says this is a complete misunderstanding, that mutations are not a normal occurrence, or let's say most of them aren't, they are mistakes, and their overall effect is destructive, even though this may not show up for quite some time. There ARE, however, thousands of known genetic diseases, and only a tiny number of mutations that are even claimed to confer any known benefit, and in most cases the benefit is a trade-off with another disease, such as malaria protection by sickle cell anemia. This looks like a thoroughly inadequate method for producing viable genetic material. And again, this is a plank in a creationist model. The facts fit the model of life's actually deteriorating rather than improving in any way.

Your view is meaningless. What matters is the evidence, and you ignore it.

•The ToE also proposes of course that mutations make up for any reduction in genetic diversity. My YEC model says 1) mutations hardly ever IF ever make DNA that acts like normal functioning DNA. The best it can do is manage not to change things, but then what do you have? Nothing really. And 2) if mutations did add genetic diversity of a valid kind to a new population, all they could add is an allele to replace another allele and one or the other is going to get selected to make up the overall "look" of the population and in the end since one gets selected out there is nothing that can really be called an increase in genetic diversity.

Your model is meaningless. What matters is the evidence, and the evidence demonstrates that mutations cause species to diverge and increase their genetic variability.

•The ToE says evolution has created everything that now lives and that this has been going on for many millions of years.

The ToE says that biological reproduction has created everything that now lives. You have been taught about the birds and the bees, have you not?

•The ToE's evidence includes the fossil record which is remarkably sorted from bottom to top according to what seems to be a hierarchy of development from more primitive to more advanced or modern (certainly complexity is not the criterion since the "lower" creatures are often amazingly complex). Of course one could wonder why evolution would operate in any particular identifiable direction onwards and upwards since one of its cardinal "tenets" is "fitness" which shouldn't imply any particular direction of adaptive traits, but it does have to be admitted that it LOOKS plausible if you allow for that idea and it seems to defeat the YEC idea that the worldwide Flood of Noah explains all the strata and their fossil contents. Nevertheless the Flood does remain the YEC alternative model to the Geologic Column, and it does have explanatory power.

Fossils fall into a nested hierarchy, just as the theory predicts. You have never been able to explain this away.

Edited by Taq, : No reason given.

Edited by Taq, : No reason given.


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Coyote
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Posts: 5944
Joined: 01-12-2008
Member Rating: 3.8


(2)
Message 214 of 233 (720103)
02-20-2014 10:58 AM
Reply to: Message 207 by Faith
02-20-2014 3:31 AM


Re: Just some examples of assumptive mystification versus genuine science
It just occurred to me that you're probably complaining that I used the word "unproved" after you told me how I'm supposed to think about it? I did answer that, it's the most natural word that comes to mind, but if it matters so much, would you prefer it if I said "unverified" or "unconfirmed" assumptions or something along those lines?

I advise you maybe ten times over the months that science doesn't deal with proof and you just ignore my posts and blithely continue on using terms incorrectly.

We all use terms incorrectly once in a while, but what you demonstrate is that you are unwilling to learn even the rudiments of science and how it works.

And then you proceed to lecture the rest of us on how we should be doing science.

What a joke!


Religious belief does not constitute scientific evidence, nor does it convey scientific knowledge.

Belief gets in the way of learning--Robert A. Heinlein

How can I possibly put a new idea into your heads, if I do not first remove your delusions?--Robert A. Heinlein

It's not what we don't know that hurts, it's what we know that ain't so--Will Rogers

If I am entitled to something, someone else is obliged to pay--Jerry Pournelle

If a religion's teachings are true, then it should have nothing to fear from science...--dwise1


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 Message 207 by Faith, posted 02-20-2014 3:31 AM Faith has responded

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Faith
Member
Posts: 25890
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 215 of 233 (720139)
02-20-2014 12:15 PM
Reply to: Message 214 by Coyote
02-20-2014 10:58 AM


Re: Just some examples of assumptive mystification versus genuine science
I've answered you about the word "proof," that I think it's just a way to rationalize pretending that evolution is scientific in the same sense that the hard sciences are. If you disallow the idea of "proof" you also disallow that distinction. You apparently haven't read anything I said in answer to you about that. But if you are going to insist, I can use other terms like "verification," or "validation" or "confirmation."

Edited by Faith, : No reason given.


This message is a reply to:
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Replies to this message:
 Message 216 by Taq, posted 02-20-2014 12:46 PM Faith has responded
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Taq
Member
Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


(1)
Message 216 of 233 (720149)
02-20-2014 12:46 PM
Reply to: Message 215 by Faith
02-20-2014 12:15 PM


Re: Just some examples of assumptive mystification versus genuine science
I've answered you about the word "proof," that I think it's just a way to rationalize pretending that evolution is scientific in the same sense that the hard sciences are. If you disallow the idea of "proof" you also disallow that distinction. You apparently haven't read anything I said in answer to you about that. But if you are going to insist, I can use other terms like "verification," or "validation" or "confirmation."

Evolution is no different than any theory in any of the hard sciences. All theories rely on testing of hypotheses and induction, just like evolution.


This message is a reply to:
 Message 215 by Faith, posted 02-20-2014 12:15 PM Faith has responded

Replies to this message:
 Message 218 by Faith, posted 02-20-2014 3:15 PM Taq has responded

  
JonF
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Posts: 3898
Joined: 06-23-2003
Member Rating: 3.2


(1)
Message 217 of 233 (720161)
02-20-2014 3:15 PM
Reply to: Message 215 by Faith
02-20-2014 12:15 PM


Re: Just some examples of assumptive mystification versus genuine science
Sorry, Faith, but there is no proof in any science. Just varying degrees of support and confidence. That's just a fact.

E.g. the age of the Earth is not proven but it is so well supported that there is no actual possibility that it will be disproven. It is as solid as the Sun coming up tomorrow. But it has not been proven.


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Faith
Member
Posts: 25890
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 218 of 233 (720162)
02-20-2014 3:15 PM
Reply to: Message 216 by Taq
02-20-2014 12:46 PM


Re: Just some examples of assumptive mystification versus genuine science
So you all say.

Against the evidence, however.


This message is a reply to:
 Message 216 by Taq, posted 02-20-2014 12:46 PM Taq has responded

Replies to this message:
 Message 219 by Taq, posted 02-20-2014 3:48 PM Faith has responded

    
Taq
Member
Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


(2)
Message 219 of 233 (720168)
02-20-2014 3:48 PM
Reply to: Message 218 by Faith
02-20-2014 3:15 PM


Re: Just some examples of assumptive mystification versus genuine science
Against the evidence, however.

What evidence? It would be a refreshing change if you actually presented some.

What evidence did you present with respect to ERV's? From what I could see, all you had was hot air with no references to any scientific papers or evidence. None. I present real scientific studies and you present . . . nothing.


This message is a reply to:
 Message 218 by Faith, posted 02-20-2014 3:15 PM Faith has responded

Replies to this message:
 Message 220 by Faith, posted 02-20-2014 7:52 PM Taq has responded

  
Faith
Member
Posts: 25890
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 220 of 233 (720200)
02-20-2014 7:52 PM
Reply to: Message 219 by Taq
02-20-2014 3:48 PM


Re: Just some examples of assumptive mystification versus genuine science
The evidence of the ERVs was undecipherable, so I asked if you'd please put it into your own words.
This message is a reply to:
 Message 219 by Taq, posted 02-20-2014 3:48 PM Taq has responded

Replies to this message:
 Message 221 by Taq, posted 02-21-2014 11:00 AM Faith has responded

    
Taq
Member
Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


Message 221 of 233 (720283)
02-21-2014 11:00 AM
Reply to: Message 220 by Faith
02-20-2014 7:52 PM


Re: Just some examples of assumptive mystification versus genuine science
The evidence of the ERVs was undecipherable, so I asked if you'd please put it into your own words.

Actually, this might serve as a good introduction to some other concepts in genetics and molecular biology. We will take this step by step so that you can ask questions if you need any clarification.

First, let's take a look at the genome of a generic retrovirus.

As you can see, the retroviral genome is pretty simple. You have two genes, gag and env, that produce proteins that are found on the outside of the viral particle. You also have pol which is responsible for producing a series of proteins that copy and insert the retroviral genome into the host genome. Then we have the LTR's on either side (LTR stands for long terminal repeat), kind of like bookends. They are made up of a repeating sequence of DNA.

Here is an important concept to understand as it becomes important later. When a retrovirus inserts into the host genome it copies one of the LTR's to produce the LTR on the other side. This means that when the retrovirus inserts the LTR's are identical in sequence.

Once the retrovirus inserts into the genome, the LTR's act as promoters for the retroviral genes which in turn results in the production of new viral particles. Here is a diagram describing the life cycle of a retrovirus.

As you can see, the retroviral genome becomes a permanent part of the host genome, and new retrovirus particles are produced from that endogenized retrovirus. This is where we get the acronym ERV which stands for endogenous retrovirus. These are retrovirus that have become endogenous to the host genome due to integration.

Any questions so far?

Edited by Taq, : No reason given.

Edited by Taq, : No reason given.


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 Message 220 by Faith, posted 02-20-2014 7:52 PM Faith has responded

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Faith
Member
Posts: 25890
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 222 of 233 (720649)
02-25-2014 11:08 PM


Mouse Genetics
Taq: I'm bringing our discussion of the pocket mice and related issues from the ecology thread to this thread where maybe we can get into some of the general genetics questions and relieve RAZD of an unwelcome subtopic.

As usual, all you are doing is ASSERTING that mutations are the cause of genetic changes.

[Taq] We OBSERVE that mutations are the cause of genetic changes.

Funny then that all you've done is declare it rhater than show such observations.

The evidence does not prove that mutation caused any of it, such as the blackness of the pocket mice. All that is necessary is that a normally-occurring recessive allele become paired up [abe]: and prolific in the population under selection pressure, and perhaps there are other genetic routes to the same result, but mutation does not have to be one of them.

[Taq] The black allele is a dominant trait. You would know that if you had read the paper that I referenced.

Well, this topic has come up before and I vaguely remember that fact anyway. But this fact doesn't necessarily end the discussion. Fur color is one of those traits that is often governed by more than one gene and when that is the case the pattern of dominant-recessive at one gene may not be the dominating influence. I'm not sure how this works, but maybe we could discuss it here.

I did find a couple of links that may or may not be relevant. One is about Rock Pocket Mice but it mostly describes the traits themselves, the "light" type and the "dark" type, and doesn't get much into the underlying genetics, though it does mention that both dominant and recessive alleles are maintained in a population.

The other is about general Mouse Genetics and it shows that black and white parents produce many "agouti" colored offspring. Black is dominant and white doesn't occur until a black is paired with an agouti.

It isn't said but the very existence of the agouti suggests that more than one gene is involved.

This is for black and white not "light" and "dark" and I'm not sure whether we're talking about two different genetic pictures or if the same principles apply, but if it's the same situation the hard thing to explain would be the light mice rather than the dark, because they would be recessive and if only one gene governs the color it would have to be paired to produce it. But if the statement from the first link is correct that both dominant and recessive alleles remain in the population then we can assume that the alleles for dark are in the light population. The D for dark would be rare in the population but you could still get a combination of Dl with ll which would most often always produce the light type, and also even the occasional Dl with Dl which would produce the light type half the time.

Then what happened when the dark were selected for the lava area would have been the favoring of the DD type and the loss of the ll type. If other genes are involved, however, there could be other factors that produce the light (or dark) even more often. I may not have the clearest grasp of how all this works but that's one reason I brought it to this thread.

Also, the black lava is much younger than the desert that surrounds it. The black allele is strongly selected against in the light colored desert to the point that even the dominant black allele can not be found in populations found any decent distance away from the black lava fields.

This is not the case of a recessive gene becoming prominant. It is dominant, and it doesn't exist in the light colored population,

How do you know this? It could be rare rather than nonexistent.

and would not have existed for any appreciable time before the appearance of these black lava islands. The genetic evidence clearly shows that it is the emergence of a mutant allele in the recent past.

The fact that the dark allele didn't show up very often in the population isn't proof that it wasn't there, it was merely selected against.

======================================================
[ABE]: All the above is not completely satisfactory and I've been thinking more about it. If you get a mutation, this one dark allele, you are also getting a dark colored mouse right away if it's passed on because this allele is dominant. So you've got, what, one or a few dark mice in a litter or what? And where is this occurring? Is it occurring in the light population or have some of the light colored mice ventured onto the lava already so the dark mice are born there or what? You are going to have to have some mice exposed to predators whether the dark ones in the light population or the light ones against the lava.

Is that one mutation enough to produce the new population of dark mice? It's possible I guess. Since it's dominant you'd have a Dl individual with the mutation plus ll so you could easily get a couple of Dls in the next generation, both of course dark mice. If they are in the light colored population and manage to survive they may produce some more Dls in the next generation and by the third and fourth some DDs as well.

But again, one way or another one of the colors is going to be vulernable to being selected out by predators.

That being the case, this really isn't a strong argument for mutation at all, but for the rare occurrence of a normally occurring D in the population from time to time. When the selection pressure occurs it would be when some of the light population have ventured onto the lava with a few darks among them. The lights get picked off and the darks go on to multiply.

One way or another you are going to have to have a few darks among the lights and a few lights among the darks and that's only really likely to happen for purposes of selection if both are already present in the population. [/ABE]

====================================================

Or perhaps you can tell us why the observed mechanisms of mutation could not produce the black allele.

[ABE]: After writing the above "ABE," I see that one argument against mutation is that a single dark allele is going to produce maybe a couple of dark baby mice which would expose them to predators whereas a regularly occurring dark allele already in the population would be producing dark babies from time to time anyway, and the chances for their survival are greater than the one mutation's chances. So I conclude that there's really no good argument for mutation as the source of the dark type. [/ABE]

Well, the observed mechanisms of mutation are usually described as mistakes, and the various ways they occur certainly look to me like mistakes and nothing I'd expect to happen *normally* to the amazingly complex and incredibly well organized DNA system.

Plus the fact that you all acknowledge that mutations are the cause of an amazing number of genetic diseases, not ALL of which are "selected out" by the way although that is the accepted wisdom. I just saw an article about a very rare genetic disease that two brothers didn't know they had until adulthood when now their lives are threatened by something they didn't even know they had, this Alport syndrome.

PLUS all those "neutral" mutations which are observed, which as far as you know do nothing, which is rather odd, again, in such an incredibly complex and amazingly organized genetic system.

PLUS the fact that you really don't KNOW of many clearcut beneifts of mutations, and even those you can point to are rather iffy.

PLUS the fact that the mutation would have to occur specifically at the gene for fur color in time to produce the favored dark mouse and occur in mice that have ventured onto the lava field rather than in the light mice where it would only be selected against. What are the odds?

Plus the fact that it would have to produce the right sequence so as not to mess up the fur color gene completely. Maybe that's not too hard since a "neutral" mutation wouldn't change much anyway, but then wouldn't we expect just another "light" to show up? How is it going to produce enough of a change to produce a dark over a light? Odds again seem to be a problem here.

There are a few reasons for you.

Edited by Faith, : No reason given.

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Replies to this message:
 Message 224 by Taq, posted 02-26-2014 11:30 AM Faith has responded

    
Faith
Member
Posts: 25890
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 223 of 233 (720652)
02-25-2014 11:37 PM
Reply to: Message 221 by Taq
02-21-2014 11:00 AM


retrovirus
Thanks for the info about the retrovirus. I may have some questions later.

Edited by Faith, : No reason given.


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Taq
Member
Posts: 7034
Joined: 03-06-2009
Member Rating: 3.7


(1)
Message 224 of 233 (720685)
02-26-2014 11:30 AM
Reply to: Message 222 by Faith
02-25-2014 11:08 PM


Re: Mouse Genetics
Funny then that all you've done is declare it rhater than show such observations.

The genetic basis of adaptive melanism in pocket mice

It is demonstrated in the paper above.

Well, this topic has come up before and I vaguely remember that fact anyway. But this fact doesn't necessarily end the discussion. Fur color is one of those traits that is often governed by more than one gene and when that is the case the pattern of dominant-recessive at one gene may not be the dominating influence. I'm not sure how this works, but maybe we could discuss it here.

In the study, the mutant allele correlated 100% with the dark fur color, even in mice that were carrying a single copy (i.e. heterozygotes). The mutations are also found in the same gene that governs melanism in humans.

The fact that there are many genes that can mutate to change fur color only strengthens my case.

It isn't said but the very existence of the agouti suggests that more than one gene is involved.

This is for black and white not "light" and "dark" and I'm not sure whether we're talking about two different genetic pictures or if the same principles apply, but if it's the same situation the hard thing to explain would be the light mice rather than the dark, because they would be recessive and if only one gene governs the color it would have to be paired to produce it. But if the statement from the first link is correct that both dominant and recessive alleles remain in the population then we can assume that the alleles for dark are in the light population. The D for dark would be rare in the population but you could still get a combination of Dl with ll which would most often always produce the light type, and also even the occasional Dl with Dl which would produce the light type half the time.

Then what happened when the dark were selected for the lava area would have been the favoring of the DD type and the loss of the ll type. If other genes are involved, however, there could be other factors that produce the light (or dark) even more often. I may not have the clearest grasp of how all this works but that's one reason I brought it to this thread.

This goes back to what I was saying before. The black fur color is deleterious in the light colored desert because they stick out as much as the light colored mice do on the black lava. It is selected against. This is why you don't find the DL or DD individuals in the light colored desert.

This is also why this trait could not have been present in the population before the recent production of the black lava fields. As soon as the mutation occurred (or within very few generations), it would have been selected against and would have disappeared from the population. The lava fields are very recent relative to the brown desert. On top of that, the different genetic mutations in two different populations that both produced black fur also supports this conclusion.

How do you know this? It could be rare rather than nonexistent.

The selection is strong enough that it overcomes the dominance of the allele.

That being the case, this really isn't a strong argument for mutation at all, but for the rare occurrence of a normally occurring D in the population from time to time. When the selection pressure occurs it would be when some of the light population have ventured onto the lava with a few darks among them.

Then explain why the two separate populations have different mutations that each produce dark fur.

"Interestingly, another melanic population of these mice on a different lava flow shows no association with Mc1r mutations, indicating that adaptive dark color has evolved independently in this species through changes at different genes. "
http://www.pnas.org/content/100/9/5268.long

These two lava fields are separated by hundreds of miles of light colored desert. The facts support de novo mutations appearing in the two different poplations, not a single pre-existing trait that was then selected for at two points.

ABE: There is also the fact that the dark allele has less sequence variation than the light allele.

"Finally, the pattern of nucleotide variation observed among Mc1r alleles from the Pinacate site suggests the recent action of positive selection. Thirteen polymorphic sites are variable among the light haplotypes, whereas only one site is variable among the dark haplotypes (Table 1). The ratio of variant to invariant sites is significantly different between dark and light alleles (1/953 and 13/941, Fisher's exact test, P < 0.01). "
http://www.pnas.org/content/100/9/5268.long

If the dark allele had been around as long as the light allele then we would expect to see the same sequence variation, but we don't. There is much less variation in the dark allele which is consistent with the recent emergence of the allele.

Well, the observed mechanisms of mutation are usually described as mistakes, and the various ways they occur certainly look to me like mistakes and nothing I'd expect to happen *normally* to the amazingly complex and incredibly well organized DNA system.

Plus the fact that you all acknowledge that mutations are the cause of an amazing number of genetic diseases, not ALL of which are "selected out" by the way although that is the accepted wisdom. I just saw an article about a very rare genetic disease that two brothers didn't know they had until adulthood when now their lives are threatened by something they didn't even know they had, this Alport syndrome.

PLUS all those "neutral" mutations which are observed, which as far as you know do nothing, which is rather odd, again, in such an incredibly complex and amazingly organized genetic system.

PLUS the fact that you really don't KNOW of many clearcut beneifts of mutations, and even those you can point to are rather iffy.

PLUS the fact that the mutation would have to occur specifically at the gene for fur color in time to produce the favored dark mouse and occur in mice that have ventured onto the lava field rather than in the light mice where it would only be selected against. What are the odds?

Plus the fact that it would have to produce the right sequence so as not to mess up the fur color gene completely. Maybe that's not too hard since a "neutral" mutation wouldn't change much anyway, but then wouldn't we expect just another "light" to show up? How is it going to produce enough of a change to produce a dark over a light? Odds again seem to be a problem here.

There are a few reasons for you.

That doesn't even come close to answering the question.

Just because they are mistakes does not prevent them from producing beneficial changes. Just because some changes are neutral or detrimental does not prevent other changes from being beneficial.

There are 40 million mutations that separate humans and chimps. Do you really think that none of those differences are beneficial to humans or chimps?

Edited by Taq, : No reason given.

Edited by Taq, : No reason given.


This message is a reply to:
 Message 222 by Faith, posted 02-25-2014 11:08 PM Faith has responded

Replies to this message:
 Message 225 by Faith, posted 02-26-2014 1:49 PM Taq has responded

  
Faith
Member
Posts: 25890
From: Nevada, USA
Joined: 10-06-2001
Member Rating: 1.1


Message 225 of 233 (720687)
02-26-2014 1:49 PM
Reply to: Message 224 by Taq
02-26-2014 11:30 AM


Re: Mouse Genetics
How did the mutant allele occur just in time to form a dark population of mice? Mutations ARE random and unpredictable aren't they? Or not? You get this allele JUST IN TIME, see, because one of your arguments that it IS az mutation is the fact that it's dominant, so the idea is that the population previously had NO allleles for dark fur. Now it has one. It occurs in the germ cell, right? Because it gets passed on. Just when the light mice are getting to the lava field apparently. So it gets passed on. It's a Dl, it will have to pair with an ll. Hey by the way how does that ONE germ cell with the mutant allele happen to get passed on anyway?

So it pairs with an ll and could make four babies, two lls and two Dls. At best.

And what's to stop this predator that has kept the population light forever from just picking off those two little dark babies as soon as they are born? Or is this happening on the lava field? If so, how is the light one managing to escape the predators long enough to produce the babies?.

As you say there is apparently more than one gene that can mutate to make dark fur color. The problem is that the odds are against this happening for starters, just in time for the lava field, then they are against the offspring surviving assuming they get produced, then they are against them growing up to make more dark mice.

So for whatever reason that other gene is the one where the rare allele happened to show up in that other population. The rare naturally occurring allele, not a mutation. The odds are far more against mutation than against my scenario.

The odds aren't a LOT better for built in alleles but at least they would already have been in the population and showing up from time to time so we don't have to count on luck to produce them at precisely the right moment. And it WOULD be luck, right? So far nobody has said that mutations show up exactly where there are needed when they are needed, they ARE a random "mistake," or are they not?

In the case of built in alleles they'd show up just as occasionally on the lava as they did on the sand, but there they'd be selected for. But wouldn't we expect a mutation to show up in the light population on the sand? Or is that mutation just SO precocious that it waits to show up on the lava?

I don't find your arguments for mutations to be convincing. The odds are against the whole scenario. OK, I'll read your post again and think about it more but one read through still says there is no way to be sure those are mutations.


This message is a reply to:
 Message 224 by Taq, posted 02-26-2014 11:30 AM Taq has responded

Replies to this message:
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