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Author | Topic: Can Chromosome Counts Change? | |||||||||||||||||||||||
Mammuthus Member (Idle past 6503 days) Posts: 3085 From: Munich, Germany Joined: |
Sure they count as mutations.
Check out this link http://www.iephb.nw.ru/labs/lab38/spirov/hox_pro/hoxmap.html Note, amphioxus has a single Hox cluster used in segment determination..look at Drosphila, then pufferfish, and mammals. There are more and more novel Hox genes and clusters that have arisen by duplication from an ancestral Hox gene. Each Hox gene specifies a different portion of the development process and therefore, each duplication is not just more of the same thing..they have diverged since duplication and acquired novel function. This is a gain in information...and it correlates with a gain in morphological complexity. Another example of a novel protein that has arisen recently is syncytin. It is a retroviral envelope protein that is crucial to syncytiotrophoblast fusion in hominids and Old world Monkeys but not in other mammals. Thus, a key step in the development of higher primate placental development appeared only recently.
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Peter Member (Idle past 1507 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
That's why we need to drop this whole 'new information'
thing. It's not useful, and you can generate novel features just by changing or rearranging existing genes. I think someone else already asked, but what do you meanby protein family?
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blitz77 Inactive Member |
quote: Well, for example you peeps like to use the example of haemoglobin C. So we have a mutation from haemoglobin A to haemoglobin C, which are still within the same "protein family". I suppose you could call it similar to micro vs macroevolution except on a molecular level. Now, if you could show a way to mutate haemoglobin C to something say, like cytochrome C (yeah I know, they could possibly be similar enough that you evolutionists might propose that the first haemoglobin came from a mutation in cytochrome C so it might be a bad example... or maybe not), that would be a different protein family [This message has been edited by blitz77, 01-09-2004]
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blitz77 Inactive Member |
quote: But... but... that begs the question-how did the first hox gene arrive?
quote: Icic... but that doesn't answer how the retroviral protein arose.
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crashfrog Member (Idle past 1495 days) Posts: 19762 From: Silver Spring, MD Joined: |
I suppose you could call it similar to micro vs macroevolution except on a molecular level. Right, but there's no difference between micro and macroevolution, so that doesn't really explain anything. How would you tell the difference between two protiens in the same family and two protiens from different families?
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Taqless Member (Idle past 5941 days) Posts: 285 From: AZ Joined: |
Ned,
An example is a study (sorry I do not have the reference) where it was found that 40% of incarcerated violent sexual offenders actually had two(it might have been more) y chromosomes. Although a little correlative, it seemed to indicate that more testosterone was being produced and thus served as a possible explanation (still leaves 60% though).
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NosyNed Member Posts: 9004 From: Canada Joined: |
But... but... that begs the question-how did the first hox gene arrive?
So what? Why is that relevant to the issue that you first raised? The fact is that duplication and mutation produces new "information" and new phenotypes. That was the issue. Leave the goalposts alone until the game is over. Same goes for your other line on the retroviral protein doesn't it? You other description of "protein families" makes it sound like you have made up the idea. Do you have a source discussing them? One that supplies a useful, operational definition so we can tell where one starts and the other leaves off. Common sense isn't
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agrav8r Inactive Member |
Actually the mutation was the post count- but unfortunately these threads did not evole only adapt.
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Taqless Member (Idle past 5941 days) Posts: 285 From: AZ Joined: |
Hmmmm, well technically you are right. It MIGHT not result in a novel protein (why family?), but that is not necessary for the protein change to have long-reaching phenotypic implications. Not to mention that many mutations can be "linked" to another area in the gene, and even other genes. So, I think that this would constitute "new" information if not a "novel" protein.
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Rrhain Member Posts: 6351 From: San Diego, CA, USA Joined: |
Taqless writes:
quote: Reference, please? All the information I have ever been able to find on double-Y individuals shows no such indication. The only seeming biological effect is a slight increase in height. There does not seem to be any greater representation of double-Y's in the prison population than outside it. Rrhain WWJD? JWRTFM!
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blitz77 Inactive Member |
quote: It IS relevant. You mention duplication and mutation-what if you don't have a haemoglobin A to duplicate/mutate into haemoglobin C? From a creationist viewpoint a gene family would be created ex-nihilio, while from an evolutionary viewpoint all genes arose from duplication/mutation from another gene. Apart from the first of course
quote: Well, you could take the evolutionary definition of protein families. The evolutionary definition then defines protein families are families of proteins that are evolutionarily related-ie the various homologous haemoglobins found in different organisms. From the creationist viewpoint it would be similar, except that the various protein families would have arisen via mutation from the first "created kind". This has been discussed previously between Tranquillity Base and several others (a shame he's no longer on these boards ). The link is http://EvC Forum: Does gene reuse and genome plasticity have to indicate common descent?
quote: From the creationist viewpoint there is no problem with this-to quote TB, "It's clear that this is simply an example of horizontal transfer and that it does not explain how the gene itself arose."
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blitz77 Inactive Member |
quote: From both the evolutionist and creationist viewpoints, the answer would be the same-proteins that are "evolutionarily related", ie haemoglobin in various organisms today arising from a common ancestor, which in the case of creationism would be a created "kind".
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Dr_Tazimus_maximus Member (Idle past 3245 days) Posts: 402 From: Gaithersburg, MD, USA Joined: |
quote: Hi Blitz, that is a very interesting and telling statement. By that I would assume that animals that contain the same or related proteins are all descended from a "kind". However, what would you say of animals and plants descending from the same "kind". Here is some interesting infoCrystal structure of a nonsymbiotic plant hemoglobin. Hargrove MS, Brucker EA, Stec B, Sarath G, Arredondo-Peter R, Klucas RV, Olson JS, Phillips GN Jr. Department of Biochemistry, Biophysics & Molecular Biology, Iowa State University, Ames 50011, USA. msh@iastate.edu BACKGROUND: Nonsymbiotic hemoglobins (nsHbs) form a new class of plant proteins that is distinct genetically and structurally from leghemoglobins. They are found ubiquitously in plants and are expressed in low concentrations in a variety of tissues including roots and leaves. Their function involves a biochemical response to growth under limited O(2) conditions. RESULTS: The first X-ray crystal structure of a member of this class of proteins, riceHb1, has been determined to 2.4 A resolution using a combination of phasing techniques. The active site of ferric riceHb1 differs significantly from those of traditional hemoglobins and myoglobins. The proximal and distal histidine sidechains coordinate directly to the heme iron, forming a hemichrome with spectral properties similar to those of cytochrome b(5). The crystal structure also shows that riceHb1 is a dimer with a novel interface formed by close contacts between the G helix and the region between the B and C helices of the partner subunit. CONCLUSIONS: The bis-histidyl heme coordination found in riceHb1 is unusual for a protein that binds O(2) reversibly. However, the distal His73 is rapidly displaced by ferrous ligands, and the overall O(2) affinity is ultra-high (K(D) approximately 1 nM). Our crystallographic model suggests that ligand binding occurs by an upward and outward movement of the E helix, concomitant dissociation of the distal histidine, possible repacking of the CD corner and folding of the D helix. Although the functional relevance of quaternary structure in nsHbs is unclear, the role of two conserved residues in stabilizing the dimer interface has been identified.and a link to a decent paper on hemoglobin in an Actinorhizal where hemoglobin is present in concentrations approaching that of legumes. Now, the last time that I looked into it, which was a while ago, the origins of plant hemoglobin were somewhat underdispute but if I remember correctly the most likely source would be an ancient unicellular or colony organism. Does that mean that your "kind" would be roughly equivalent to early life forms discussed by the evolutions side of this debate, and if not how not? "Chance favors the prepared mind." L. Pasteur and my family motto Transfixus sed non mortis Taz
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blitz77 Inactive Member |
quote: That is assuming that God did not create hemoglobin in more than one "kind". For plants and animals God may have given slightly different types of hemoglobin, as best suited to the task. Much like as human engineers today reuse "wheels" in basically every human invention-cars, trains, cogs... you name it. Of course, that would be from a creationist perspective. From an ID perspective your proposal could be correct Now, what is interesting is this-you assume that from an evolutionary viewpoint, their similarity can be explained, while refuting that of creationism (am I right in assuming you believe this?). From an evolutionary viewpoint then, why wouldn't there be some non-homologous proteins evolving to perform the same function? Why must they be evolutionarily related? From a creationist viewpoint the similar proteins made in different "kinds" at creation may be similar because God may simply "reuse" designs for similar purposes, with "tweaks" for their particular tasks. This may then allow mutations, horizontal gene transfer, etc to allow for changes in the environment.
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crashfrog Member (Idle past 1495 days) Posts: 19762 From: Silver Spring, MD Joined: |
From both the evolutionist and creationist viewpoints, the answer would be the same-proteins that are "evolutionarily related", ie haemoglobin in various organisms today arising from a common ancestor, which in the case of creationism would be a created "kind". Back to the question you couldn't answer - how would you tell the difference between two proteins from the same family and two from a different family? How come you're still talking about "created kinds" when you couldn't even tell me what they are?
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