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Author | Topic: Did viruses precede other life? | |||||||||||||||||||||||
SUnderwood Inactive Member |
Look, for God sake if you don't understand what I'm saying read the damned website! The major issue here is your "belief" that micro-evolution by genetic allel mutation actually provides real beneficial change to the genetic structure. IT DOESN'T! Genetic faults are VERY RARE!! Yes, you see organisms with problems, (i.e. sickle cell) but consider how many hundreds of billions of cells YOU are made out of, and each person is made out of, if so-called micro-evolution had any MAJOR effect on the genetic code, it would be obvious! Cells within us would have different genetic code!
Get out of the dogmatic BOX! Read the website, at least read the Whats New section to see the gradual build up of evidence. You are an intelligent person, i can see that, but don't let yourself be trapped. The only way out is to read. You've said yourself before you haven't read much about it. Read about it and come back. I have to say its very interesting talk to you because you make me think.
quote: HGT transfers WHOLE WORKING GENES! WHOLE PROTEINS! Whole TOOLS that the cell can use. Micro-evolution provides single allel mutations, that will invariably destroy protein effectiveness (i.e. sickle cell) and the probably the organism, if it ever gets past gestation.
quote: 1st u've made an assumption that muation occurs only on non-expressed portions of the genome. Thats wrong. When it does happen it will happen more likely to expressed "working" regions. However, you've made me think a little. I would reply this: Again, random mutation is VERY RARE! The repair mechanism of cells are extremely efficient. You will notice that genetisists say there are regulator regions which change more frequently. Those areas of the genomes which ARE frequently altered via "mutation" seem to be under directed alteration by the genome itself. As yet I haven't come across a piece of research that documents the genetic alteration of a genome by "self-mutation" (except for the rearrangement of genes in general) but I think thats because no-one is looking for it.
quote: Look, please, following this link and read just this one page.Interesting links on it are * More about photosynthesis by gene transfer* Gene transfer among eukaryotes * Halobacteria can repair badly damaged DNA * More animal genes came from bacteria * Microbes have stolen some of our genes! And more. What'sNEW in Cosmic Ancestry. by Brig Klyce Panspermia is a beautiful theory. And if you're interesting in quantum physics and organic systems, its even more amazing theory than the pure genetics side can "see". Sean
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SUnderwood Inactive Member |
Hi ooook
Here is some evidenace from What'sNEW in Cosmic Ancestry. by Brig Klyce
Gene transfer among eukaryotes Two independent studies show that there have been horizontal gene transfers between parasites and their vertebrate or plant hosts. "The huge significance of horizontal gene transfer for the evolution of prokaryotes has been known for a long time, as has the large contribution that intracellular endosymbiont ancestors of mitochondria and chloroplasts have made to eukaryotic genomes.... Studies such as these show that ongoing horizontal gene transfer from a range of parasites and endosymbionts might be more important for eukaryotic evolution than we previously realized just how important remains to be seen." Nick Campbell, "Genome Evolution: Give and take" [article], p 638-639 v 5, Nature Reviews Genetics, Sep 2004.Nature - Not Found More about photosynthesis by gene transfer. In 2002, geneticists Raymond, Zhaxybayeva et al. used whole genome comparisons to conclude that photosynthesis in five groups of prokaryotes was acquired by gene transfer. In 2003, biologists at the University of Warwick found photosynthesis genes in a virus, S-PM2. Now, a team of biologists from Boston and San Diego "report the presence of genes central to oxygenic photosynthesis in the genomes of three phages from two [other] viral families...." The abstract of their writeup mildly concludes, "These gene transfers are likely to play a role in the fitness landscape of hosts and phages in the surface oceans." We note that evidence supporting gene transfer as the source for new genetic programs continues to accumulate. Meanwhile, evidence supporting a darwinian mechanism as the source for new genetic programs is lacking. Debbie Lindell et al., "Transfer of photosynthesis genes to and from Prochlorococcus viruses" [abstract], p 11013-11018 v 101, Proc. Natl. Acad. Sci. USA, 27 July 2004.Just a moment...
More animal genes came from bacteria. According to a report coming in the July 2004 issue of Trends in Genetics, genes for enzymes involved in the manufacture of important chemical messengers were transferred from bacteria to animals, perhaps half a billion years ago. The genes are essential for animal functions including learning, memory, mental alertness, sleep patterns, and allergic responses. NIH's website reports: "For the study, the researchers conducted a comprehensive search of the National Library of Medicine's genetic databases. They identified a group of genes needed to make some enzymes involved in the manufacture of the chemical messengers that cells use to communicate. The genes are present in bacteria and in vertebrate animals, but with a few exceptions, not in plants, or other complex living organisms. The search was prompted by the group's earlier observation that [another] enzyme ...was present in animals, bacteria, and yeast, but in no other living organisms. "It is not known how the genes were transferred, but [one member of the research team, David] Klein, theorizes that one form of transfer took place during the reproductive cycle, with the genes having been incorporated into either sperm or egg cells or incorporated shortly after fertilization. It's possible that the transfer could also represent a form of infection where genetic material is transferred into these reproductive cells and thereby into the entire genome of the recipient." According to our reasoning, wholly new genetic programs must be acquired by gene transfer. The new report from NIH adds to the growing list of apparent examples of this process. Examples documenting the darwinian creation of new genetic programs remain few in number and very weak. [Thanks, Newshub.] Genes Promoting Nerve, Other Cell Communications May Have Come From Bacteria, National Institutes of Health (NIH), 1 June 2004.Request Rejected Genes Promoting Nerve, Other Cell Communications May Have Come From Bacteria, ScienceDaily.com, 3 June 2004.http://www.sciencedaily.com/...ases/2004/06/040603063920.htm Viruses old as life? When virologists analyzed a hyperthermophilic virus from an archaeal host living in a Yellowstone hot spring, they found "astounding" conformational relationships linking it to known viruses of bacteria and animals. They conclude, "some viruses may have a common ancestor that precedes the division into three domains of life > 3 billion years ago." George Rice et al., "The structure of a thermophilic archaeal virus shows a double-stranded DNA viral capsid type that spans all domains of life" [abstract], Proc. Natl. Acad. Sci. USA online, 3 May 2004.http://www.pnas.org/cgi/content/abstract/0401773101v1 Organelles transfer genes, wholesale, to eukaryotes, an international team of biologists based in Australia reports. This mechanism is yet another way for gene transfer to install genetic programs into eukaryotic species. Among the team's findings
"Genome sequences reveal that a deluge of DNA from organelles has constantly been bombarding the nucleus since the origin of organelles.... at frequencies that were previously unimaginable. "Phylogenetic analyses and genome comparisons show that influx of organellar DNA to the nucleus has had a marked quantitative impact on the gene content of eukaryotic chromosomes. "Translocated genes might be expressed to provide products that are targeted to all parts of the cell. "This mechanism of natural variation is unique to eukaryotic cells and was an important force in the genesis of eukaryotic genomes." Jeremy N. Timmis, Michael A. Ayliffe, Chun Y. Huang and William Martin, "Endosymbiotic Gene Transfer: Organelle Genomes Forge Eukaryotic Chromosomes" [abstract], p 123-135 v 5 n 2, Nature Reviews Genetics, Feb 2004.Nature - Not Found
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crashfrog Member (Idle past 1467 days) Posts: 19762 From: Silver Spring, MD Joined: |
Yes, you see organisms with problems, (i.e. sickle cell) but consider how many hundreds of billions of cells YOU are made out of, and each person is made out of, if so-called micro-evolution had any MAJOR effect on the genetic code, it would be obvious! Cells within us would have different genetic code! What the fuck? Exactly what sort of selection pressure do you think my individual cells experience?
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SUnderwood Inactive Member |
Read a little more. I'm saying that genetic allel mutation occur very rarely.
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crashfrog Member (Idle past 1467 days) Posts: 19762 From: Silver Spring, MD Joined: |
I'm saying that genetic allel mutation occur very rarely. Over the lifetime of an organism, yes, that's true. Over the lifetime of a population, mutations are copious.
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SUnderwood Inactive Member |
No, allel mutation is not cupious. A lot of mixing occurs due to fertilisation, but mutation of allels does not occur often. Don't get the two confused.
And you can't talk about over the lifetime of a population. thats doesn't make sense. Of a species, well, yes, mutation of allels does occur quite often over millions of years or so, and most die because of it, so are a hinderance to evolution (or a benefit, as that mutation was deleted and not passed on). This message has been edited by SUnderwood, 09-29-2004 02:04 PM
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crashfrog Member (Idle past 1467 days) Posts: 19762 From: Silver Spring, MD Joined: |
No, allel mutation is not cupious. A lot of mixing occurs due to fertilisation, but mutation of allels does not occur often. Over the lifetime of a population, it does occur often. According to Molecular Evolution: A Phylogenetic Approach (Page, Colmes; Blackwell Science, 1998), a graduate level genetics text, the average number of synonymous substitutions in mammalian nuclear DNA is about 3.5e-9 per base, per year. There's a lot of bases, and a lot of mammals. 3 or 4 per billion bases every year is a lot of mutations to a population.
And you can't talk about over the lifetime of a population. thats doesn't make sense. In fact, viewing it from the perspective of populations is the only way that evolution makes sense. Populations grow and divide; it makes perfect sense to talk about the "lifetime" of a population. This message has been edited by crashfrog, 09-29-2004 02:06 PM
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Rei Member (Idle past 7013 days) Posts: 1546 From: Iowa City, IA Joined: |
Not to mention how significant one BP mutation can be. It's always interesting when people trace back the presence of a mutation - say, a human tail, or an XY female - to its genetic cause. Often there's only a few BP mutation that was ultimately the reason for the change.
"Illuminant light, illuminate me."
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SUnderwood Inactive Member |
I take your point. Synonymous substitutions is more frequent than I had thought. But codon substitutions is still deleterious. The paper to which you refer is interesting in its conclusions, that amino acid substitution is deleterious, whilst nucleotide subsitution (depending on its synonymity) is not, necesarily. My apologies, I have mixed up the codons and allels. Thank you very much for the reference.
The paper referenced does howver provides support to the argument, that evolution, at the protein level, is a rare event, and that nucleotide mutation (and so codon change) is usually damaging. HGT, then, is still a major source of genetic information. BTW, did u read the list of references which I posted?
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crashfrog Member (Idle past 1467 days) Posts: 19762 From: Silver Spring, MD Joined: |
But codon substitutions is still deleterious. Not universally, and remember, "deleterious" is generally only meaningful in reference to environment. For instance, is a mutation conferring longer, thicker fur advantageous or deleterious? It depends on if you live in the arctic circle or the Sahara desert.
BTW, did u read the list of references which I posted? No - I'm not certain I have the background to engage you on your main point. I simply wanted to clear up some of your misconceptions.
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extremophile Member (Idle past 5595 days) Posts: 53 Joined: |
quote:Thanks. I do not consider myself a dogmatic person (although hardly someone dogmatic would admit it easily), there's a lot of things that I don't understand, and there's the way I understand things. And, in the way I understand things (that might be wrong, of course) this thing of HGT driving evolution didn't seems to make much sense. I'll keep with this further on the message, now I just want to say that there's a considerable time since I'm planning to read this site, among lots of other stuff (such as things about directed - or not - mutations). I didn't read it yet due to lack of time, not because dogmatic refusal or something. Actually, even if I was "against" this idea (but in this case I'm more curious than against), it would paradoxically increase my interest about that... it happened with creationism and some other alternatives ways of evolution that I've briefly heard (although I couldn't find much things on these yet). quote:...but, genes really work this way? Like man-made program sub-routines? Don't they generally depends on the "context" of the genome?The site provides examples of possible traits/sequences acquired this way? ... I don't want to bomb you with all the questions that came to my mind, but, anyway, just one more for this part of the post... what about phylogeny? How much the standard phylogenetic tree would be affected by this theory, or it stays the way it is? Seems to me that if HGT is more frequent and relevant than commonly thought, then many shared characters could not be due to common descent, but due to HGT. But yet I guess that the phylogenetic tree would retain the same basic look of a tree, with the addition of a tangled web of thin "veins" linking many branches... but... I have no idea yet of what could be those H-shared traits....
quote:No, I didn't, I was just making an analogy the most equivalent possible to the example that you gave, where a mutation activates unexpressed genes that were H-acquired, but instead of unexpressed genes H-acquired it could just be a "normal" sequence, that were deactivated for some reason. And, for the second case, there's, I think, the advantage of the sequence reactivated being a former activated sequence of the same lineage of organisms, so, that wouldn't be a completely odd, alien, sequence suddenly activated, which I think that doesn't differ much of mutationism/saltationism. I think that it would be a problem because the RA Fisher's analogy of the focus adjustment; the more radical a change in an organism is, the more unlikely is to fit in the actual environment, since the fitness of the parent organism obviously is due to its present phenotype. I don't discard totally "hopeful monsters", but I don't think they are the main cause of drastic changes in evolution... but I don't even know if that would be the case with H-inheritance.... That's all for while, I got to go.... but I'll read the next post and the recomended page, and hopefully, more on the site.... but, just one more question... how exactly this stuff of HGT connects with panspermia? Suddenly I realized that we didn't talked of panspermia properly, but only about stuff that can exist independently, and, maybe be some sort of support for that (yet I couldn't wonder much far how would that be) sorry if I left some part unanswered (I probably did), I'll check that later....
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Ooook! Member (Idle past 5815 days) Posts: 340 From: London, UK Joined: |
Hello SUnderwood,
Good to see this topic up and running again. A few points: As you can see from my previous posts to Razd I don't think it's unreasonable to think that HGT drove early evolution (ie before the split into the three distinct domains): the 'bushiness' of the 'tree' of life () at this stage is testament to the amount of genes whizzing from organism to organism. I also don't dispute the evidence that suggests there being a transfer of genes from symbionts to the nucleus of hosts. But I have a few reservations about making the bold claims you seem to be making.
To sum up: an interesting idea, but nothing to shout about (yet) Cheers
Edit: Got my laterals and verticals mixed up - which can be quite painful I can tell you! This message has been edited by Ooook!, 09-30-2004 10:35 AM
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Brad McFall Member (Idle past 5033 days) Posts: 3428 From: Ithaca,NY, USA Joined: |
Ah, the carnivore in me, druuuls...
It is not time for me- but WHEN IS an ANGLE not the pectoral fin handle- when it is snapping the turtle soup-- You would have had to think of the SAMPLE outside the code but within your posting discourse for one to have thought yous two confused the shape of the organism for a different environment. but then we get the the artic compared with the sahara here. Oh how I wish panbiogeography was better used. I put my record in - NO I DONT THINK VIRUSES "PRECEDED" other life. just like I think virus as AIDS is a more sociological than anthropological. I do know that cartoons were made of algebraists however.
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Lex_Luthor Inactive Member |
A virus could not precede life for the simple reason that a virus requires a host to survive.
Edited by Lex_Luthor, : No reason given.
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Chiroptera Inactive Member |
Hiya, Lex.
It is true that a virus needs a host. However, that host need not have been something that we would consider to be "life" -- the original hosts of viruses (virii?) may have been precursors that were far simpler than what we would be comfortable with assigning to the category of "living". Here is an link to an article to which I have already posted that suggests that viruses may have been an important contributor to what eventually became "life". "We must respect the other fellow's religion, but only in the same sense and to the extent that we respect his theory that his wife is beautiful and his children smart." -- H. L. Mencken (quoted on Panda's Thumb)
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