Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
6 online now:
Newest Member: popoi
Post Volume: Total: 915,807 Year: 3,064/9,624 Month: 909/1,588 Week: 92/223 Day: 3/17 Hour: 0/1


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   Beneficial Mutations Made Simple
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 5 of 52 (312368)
05-16-2006 9:22 AM
Reply to: Message 1 by IrishRockhound
05-16-2006 7:48 AM


Some recent research has shown that at least one mutation in the gene coding for Lipoprotein Lipase (LPL) produces a protein which is prematurely truncated and which appears to be more efficient in preventing atherosclerosis and cardiovascular disease than wildtype LPL (Rip, et al., 2006).
I would not typically have expected a gene like this to be particularly beneficial as I would associate it with a later stage of life than when most reproduction is occurring. However perhaps modern dieat and the increase in obesity, or the fact that many people are having children later in life have allowed this to become a target for selection.
Having said that the prevalency of the mutation, carried by ~20% of the population, suggests that its origins are considerably more ancient than the 20th century when the current lifestyle factors would have been relevant. Once again it is all to easy to make up ad hoc hypotheses which could explain some aspects of a phenomenon.
TTFN,
WK

This message is a reply to:
 Message 1 by IrishRockhound, posted 05-16-2006 7:48 AM IrishRockhound has not replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 14 of 52 (313195)
05-18-2006 12:41 PM
Reply to: Message 11 by Hyroglyphx
05-18-2006 12:07 PM


Hox proteins are thought by some to be the vehicle driving beneficial mutations.
These 'some' are presumably people who have no idea what the hell they are talking about. The Hox genes are important in body patterning and are thopugh to have an important role in the evolution of differeing body plans but to describe them as 'the vehicle driving beneficial mutations' just suggests you haven't the faintest familiarity with any of the science and are just parroting bullshit from some equally ill informed website.
The mutational screens you are talking about, presumably along the lines of the seminal work of Nusslein-volhard and Weischaus, were specifically designed to allow the identification of mutations which were embryonically lethal or otherwise easily scorable. If this isn't the sort of work you were talking about then maybe you should provide some references.
The types of mutagenesis used are also massively crude, such as mutagenic chemicals or exposure to gamma rays, the idea is to damage the dna in order to identify regions which are important in a process not to generate mutations in a way analagous to what goes on in vivo
Almost all such screens look for easily scored phenotypic characteristics, i.e. legs substituted for antennae, no eyes, severe losses or changes in character of limb, early death or failure to hatch. The only way to identify a 'bionic' fly would be to follow it through a breeding population to find out that it had improved fitness. You can easily see a lethal mutation which will never live to reproduction, or severely impair it, but it is much harder to identify one which will increase reproductive success merely by eyeballing an embryo.
PBS had a special on such mutations and showed an extra pair of wings on a fly and silently praised it. This of course was their tacit way of proving macroevolution. They neglected to mention that they were a hindrance for flying because no musculature was attached to it. It was as close to a harmful mutation as anything I could think of
Once again you miss the point. The mutations leading to a 4 winged Drosophila have never been suggested to be beneficial mutations, rather they are seen as consistent with the theory that the haltere is a derived wing and that the Diptera (2 winged flies) evolved from an ancestor with 4 wings. When going from a wing to the haltere the loss of the indirect flight muscles in the 3rd thoracic segment would be inconsequential, but obviously that loss presents a severe barrier to reverting back to a fully functioning wing.
The rest of your post just seems to be pure hand waving explanation. Your science just seems to be pure garbage, you should really provide some evidence if you expect anyone to think they aren't just your own deranged imaginings.
No one says that the probioscis evolved from a 'spare leg' and the work suggesting that there are homologies between the 2 structures could not be further from guessing (Abzhanov , et al., 2001), but I suppose you would have to actually understand any of it to know that, and you clearly don't. If you have even read any of it that is, which I sincerely doubt.
In summary, evolution relies on mutation and hopes that it will be beneficial. It has to rely on this because natural selection and genetic drift both need a gene pool from which to select from or drift within.
Practically the only remotely accurate thing in your entire post.
TTFN,
WK
Edited by Wounded King, : presentation of additional information

This message is a reply to:
 Message 11 by Hyroglyphx, posted 05-18-2006 12:07 PM Hyroglyphx has replied

Replies to this message:
 Message 45 by Hyroglyphx, posted 05-25-2006 2:03 PM Wounded King has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 16 of 52 (313625)
05-19-2006 7:08 PM
Reply to: Message 15 by mr_matrix
05-19-2006 5:13 PM


More uninformed rubbish
Please see message #13 above.
TTFN,
WK

This message is a reply to:
 Message 15 by mr_matrix, posted 05-19-2006 5:13 PM mr_matrix has replied

Replies to this message:
 Message 17 by mr_matrix, posted 05-19-2006 7:11 PM Wounded King has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 18 of 52 (313639)
05-19-2006 7:31 PM
Reply to: Message 17 by mr_matrix
05-19-2006 7:11 PM


Re: More uninformed rubbish
Wow, you read like 14 whole posts on a message board, well you must know pretty much everything about genetics by now.
All I saw in these posts (the ones that defend mutations and evolution) is just imaginary tales of a mutation having a benifit.
So you read all of the referenced material? You read the Rip, et al. paper and concluded it was an imaginary tale? Care to tell us how you reached that conclusion?
You know that the 4G/5G polymorphic form of PAL-1 isn't actually connected to Pal-1 plasma levels? How did you come by this knowledge?
What evidence do you have that pyrethroid resistant whitefly don't outcompete non-resistant whitefly under heavy insecticide application?
Those are the specific mutations which have been mentioned and rather than addressing any of them or giving any sort of reasoned argument you just close you eyes, go 'la,la,la,la,la', and think you have pulled off some debating coup somehow rebutting all these examples thorugh the sheer force of your ignorance?
Lets look at the DNA, it is a very complex structure that functions almost perfectly on its own
Whoops, wrong again! DNA is essentially a very simple structure composed of strings of only 4 nucletotide bases. On its own DNA will barely do anything, apart from maybe hybridise and hydrolyse a little. It takes a number of enzymes and other accessory proteins in order for DNA to 'function'.
and a mutation is just an accident that damages the DNA and harms the organism.
And a completely unsupported assertion to round things off. Unless that is you have some evidence that mutations are always harmful or can justify terming any change in the DNA as damage.
Some of you go as far as to claim that mutations can be useful if you use them well.
I haven't seen anyone claim this, in fact no one hs been talking about 'using' mutations at all, well or otherwise. What has been pointed out is that a mutation which may be beneficial in one environment may be detrimental in another.
TTFN,
WK

This message is a reply to:
 Message 17 by mr_matrix, posted 05-19-2006 7:11 PM mr_matrix has not replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 47 of 52 (315178)
05-25-2006 6:15 PM
Reply to: Message 45 by Hyroglyphx
05-25-2006 2:03 PM


Re: HOX and morphology
If Homeobox genes act as the architect in where what body part goes, then the implication that a chance mutation can cause an evolvement never before seen, and that it can be successful until reproduction.
This statement is a not unreasonable supoosition but through your 'magical filter of fun' somehow it equates to...
Hox proteins are thought by some to be the vehicle driving beneficial mutations.
There is a world of difference for Hox genes to be a suitable substrate for potentialy beneficial mutations linked to large scale changes in morphology and being the 'vehicle driving beneficial mutations. Absolutely non of your references support this contention, the closest they come is the BioEssays review where they say "A large body of evidence has suggested that changes in developmental gene regulation are the predominant mechanisms that sustain morphological evolution", to which I would say, "Well, Duh!".
If you aren't parroting bullshit then you must just be producing it de novo by completely failing to understand what you read or exaggerating it to produce inflated claims. Merely posting the links doesn't show that they support you claim and reading them shows that they don't. Do you not notice that none of the direct quotes you posted actually support your claim?
These abnormal limbs are not functional, but their existence demonstrates that genetic mistakes can produce complex structures, which natural selection can then test for possible uses.
This particular bit of nonsense at least is not your own, the big problem is the 'complex structures' part which suggests that the complex structures spring fully formed from nowhere rather than being what they are, duplications of already extant limb structures.
TTFN,
WK

This message is a reply to:
 Message 45 by Hyroglyphx, posted 05-25-2006 2:03 PM Hyroglyphx has replied

Replies to this message:
 Message 48 by Hyroglyphx, posted 05-25-2006 9:26 PM Wounded King has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 49 of 52 (315229)
05-26-2006 2:20 AM
Reply to: Message 48 by Hyroglyphx
05-25-2006 9:26 PM


Re: HOX and morphology
Every last one of those papers describe, in great detail, Hox being one of the possible pathways for morphology as it relates to an evolutionary process. Furthermore, I don't know what your aversion towards it is. If this isn't what you believe, that's great, because nor is it what I believe. I said that some believe that it is the driving vehicle for evolution.
Can you really not see the enormous disconnect between the one thing and the other? How can your mind work that you can type out something like 'Hox being one of the possible pathways for morphology as it relates to an evolutionary process' several times and then suddenly leap back to your bullshit claim that therefore scientists are saying that "Hox proteins are thought by some to be the vehicle driving beneficial mutations."
Your lack of erudition on this matter doesn't negate the dissertations I presented.
Not a single one of your references has backed up the bullshit claim you made. Apart from the fact that I disagree with you exactly how do you think I have displayed a lack of erudition? Should I have provided a list of reference not saying that "Hox proteins are thought by some to be the vehicle driving beneficial mutations."? Why bother, you have done it for me. Your own raplies are full of statements which your papers show and not a single one of them equates to "Hox proteins are thought by some to be the vehicle driving beneficial mutations.". Just because you post a whole lot more references not saying that doesn't somehow support your cllaim. You could have a 1000 such references not sayingit and you still wouodn't have substantiated the claim that scientists say that "Hox proteins are thought by some to be the vehicle driving beneficial mutations." Just look back at the much more qualified statements you have derived from your references. Especially since one refers to developmental gene regulation which is a much broader category than either Hox or homeobox genes.
If you think you are giving me an instructional lecture on evo-devo then you are deluded. I live and breathe evo-devo on a daily basis.
Yeah, exactly. They aren't functional, which is why I have been stating that the Drosophila has thus far not been able to reproduce 'good mutations,' but rather injurious ones that would certainly eliminate them in the wild due to these deformities.
Any chance you might address my non-erudite points on the nature of the mutational screens or maybe give us a reference for your 80 year screening project if you aren't thinking of the Nusslein-Volhard/Weischaus screens and subsequent similar screens. If you could show that this 80 year program was to look for beneficial large scale morphological changes it would be a good step in making your argumnet less weak. Otherwise you might qualify your statement with "..in a mutational screen designed to look for embryonic lethal abnormalities under an abnormally heavy mutagenic burden."
TTFN,
WL

This message is a reply to:
 Message 48 by Hyroglyphx, posted 05-25-2006 9:26 PM Hyroglyphx has replied

Replies to this message:
 Message 50 by Hyroglyphx, posted 05-26-2006 12:32 PM Wounded King has replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 51 of 52 (315372)
05-26-2006 12:47 PM
Reply to: Message 50 by Hyroglyphx
05-26-2006 12:32 PM


Re: HOX and morphology
I'm not sure how to continue when you seem incapable of admitting that your initial claim was wildyly exaggerated and keep shifting the goalposts to something more limited and reasonable.
It is insane to ask why I deny that...
Hox genes have been 'implicated' as 'CENTRAL' to the 'EVOLUTION of animal body plan diversity
When that isn't what you said in the first place that I then disagreed with. Being 'central to' something is not the same as being the driving vehicle of something, the 'evolution of animal body plan diversity' is not the entirety of evolution and it certainly doesn't say anything at all about beneficial mutations specifically which was the major thing I was criticising as being totally out of place in your initial claim.
Why, even after I provided a mound of evidence, you still felt the need to argue is beyond me as well. Are you a polemicist? Does arguing, just for the sake of arguing, fancy some penchant of yours?
No but having my questions avoided in such a high handed arrogant manner does encourage my stubborn streak. You didn't address a single one of the more significant points I made in my initial response to you in Message 14, instead you go off on one trying to justify a totally exaggerated strawman claim you attribute to 'some' and proceed to post umpteen references absolutely none of which support that strawman claim.
Just to remind you once again the original claim was...
Hox proteins are thought by some to be the vehicle driving beneficial mutations.
Now why not go back and actually address my points about the nature of mutational screens or provide a reference for the proboscis having been thought to derive from a 'spare' leg, or something more worthwhile than this pointless repetition of supposed support for your nonsense claim.
*ABE* Or am I just been needlessly pernickity, any lurkers feel like weighing in? Is NJ's claim consistent with the references he's posted and I'm just to stubborn to see it? Has NJ sufficiently substantiated his claim?
TTFN,
WK
Edited by Wounded King, : No reason given.

This message is a reply to:
 Message 50 by Hyroglyphx, posted 05-26-2006 12:32 PM Hyroglyphx has not replied

Replies to this message:
 Message 52 by Jazzns, posted 05-26-2006 1:19 PM Wounded King has not replied

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024