Mutation
- This topic has 20 replies, 7 voices, and was last updated 15 years, 8 months ago by
MrMistery.
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May 7, 2005 at 12:27 pm #858
victor
ParticipantDo you know how many percent possibility of having good mutation from all those mutation that happen to soma cells or gamet cells..? 😕 .And the second question is which is causing greater loss? is it gene mutation or chromosome mutation??
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May 8, 2005 at 4:51 pm #22252
thank.darwin
ParticipantI don’t know the exact percent – It is a lot lower than the chance of the mutation being neutral or harmful? Does anyone know an exact number?
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May 8, 2005 at 5:58 pm #22258
MrMistery
ParticipantNobody knows that number because it doesn’t exist. How do you know when a mutation is benefical, neutral or harmful? If the organism is better adapted to the environment than it makes more “children” and the gene perpetuates itself-benefical mutation. So, it really depends on the environment. The exact same mutation can be harmful for an organism living in an environment and benefical for an organism of the same species living in another environment.
Example: in the places where malaria lurks at every turn you can detect about 20% has Aa heterozygotus, a being the gene that causes falciform anemia. These individuals have been favoured by evolution cause plasmodium malaria can not live in their bloodIf you require more info on this process let me know
Regards,
Andrew -
May 9, 2005 at 10:07 am #22276
thank.darwin
ParticipantThanks MrMistery – I had never looked at it that way…
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May 11, 2005 at 8:08 pm #22384
MrMistery
ParticipantThat’s what i’m here for 😀 😀
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May 11, 2005 at 9:05 pm #22391
Jelanen
ParticipantAnd the chance of a mutation being passed onto offspring is even lower since mutations are recessive and unless the other parent is a carrier or also a mutant, theres a good chance the mutation won’t show up in the F1
-Jelanen -
May 11, 2005 at 9:10 pm #22393
canalon
Participantquote Jelanen:And the chance of a mutation being passed onto offspring is even lower since mutations are recessive and unless the other parent is a carrier or also a mutant, theres a good chance the mutation won’t show up in the F1I have nothing handy to prove that but I think that all mutations are not necessarily recessive. If I remember correctly Sickle cell anemia is due to a mutation and it is co-dominant.
And I totally approve Andrew’s answer. Beneficial or harmfull for a mutation depend a lot from the environment.Patrick
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May 11, 2005 at 9:18 pm #22394
Jelanen
ParticipantI absolutely would not describe sickle cell anemia as a mutation. In malarial parts of the world, being heterozygous confers a greater survival rate than either of the homozygous phenotypes. Both purple and white pea flowers are present in a population, one is dominant over the other, but is the recessive a mutation or just another phenotype? Besides, mutations are generally defined by what came first, so what actually came first….the “normal” or the “abnormal” heme? While I may have slightly mispoke when I said mutations are recessive, it is true that the vast majority of them are recessive.
-Jelanen
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May 12, 2005 at 1:37 pm #22415
canalon
Participantquote Jelanen:I absolutely would not describe sickle cell anemia as a mutation. In malarial parts of the world, being heterozygous confers a greater survival rate than either of the homozygous phenotypes. Both purple and white pea flowers are present in a population, one is dominant over the other, but is the recessive a mutation or just another phenotype? Besides, mutations are generally defined by what came first, so what actually came first….the “normal” or the “abnormal” heme? While I may have slightly mispoke when I said mutations are recessive, it is true that the vast majority of them are recessive.Ok the problem is the definition of mutant vs wild type, then. In the Sickle celle anemia I would definitely call the (I hope I’m not wrong) S-Hemoglobin a mutant. Why? Because if it were the wt, I do not think that there would be human beings any more. And I bet that if you compare Hemoglobin and S-hemoglobin to our cousins the apes, you’ll see that the S-type would not match (except maybe with a Jaguar… sorry).
Anyway “new phenotypes” can only arise through mutation (in the largest definition: point mutation, horizontal transfer, gene replication,…). And there is no rule wether a mutation should be dominant or recessive or whatever as far as I know. It completely depends on where it happens. A mutation that would cause the over expression of one gene where or when it should be silenced could easily be dominant. As wether it would be benificial or not, as said earler, it completely depends on the environment.
Hope I made my self clear
Patrick
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May 12, 2005 at 2:54 pm #22416
Jelanen
ParticipantOk, thats it, now I’m gonna have to lay the smackdown. When I get home later tonight (at work atm), I’ll break out one of my 3-4 genetics books and start quoting. That will end the recessive mutation thing.
As far as the which is the wild type and which is the mutation, that conversation is effectively over since I don’t consider non-human primates my “cousins”. Since we aren’t going to agree on that point, its not possible for me to argue which is the mutation by following that line of reasoning. I’m going to stay by the claim that SSA isn’t as much a mutation as it is an alternative genotype.
-Jelanen
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May 12, 2005 at 3:23 pm #22422
canalon
Participantquote :Ok, thats it, now I’m gonna have to lay the smackdown. When I get home later tonight (at work atm), I’ll break out one of my 3-4 genetics books and start quoting. That will end the recessive mutation thing.Prove me wrong, I’d be delighted. I don’t have any genetics textbook at hand, cause I am also in the lab and we deal bacteria, where recessive/dominant are not that common 🙂
As I said Mutations can be anything (dominant, recessive, co-dominant) depending on where they take place. But I do agree that in a diploid organism, most of the mutations are probably recessive.quote :As far as the which is the wild type and which is the mutation, that conversation is effectively over since I don’t consider non-human primates my “cousins”. Since we aren’t going to agree on that point, its not possible for me to argue which is the mutation by following that line of reasoning. I’m going to stay by the claim that SSA isn’t as much a mutation as it is an alternative genotype.If you are not conviced that evolution took place, and that apes are related to us, it is indeed imposible to use molecular evolution to prove my point. And since I do not believe that alternative genotypes could have arisen without a mutational event, I think that discussing the matter is pointless. 🙄
But I would still be interested to know what differnec you make between mutation and alternative genotype… Maybe a good starting point for a new thread.Cheers
Patrick
Patrick
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May 12, 2005 at 6:13 pm #22428
Poison
ParticipantAs much as I know, sickle cell anemia is a mutation. A person with sickle cell anemia has the tirplet GTG instead of GAG in the gene for hemoglobin. This base situation causes a valine to replace a glutamic acid in the hemoglobin. So…. Why don’t we call this a mutation? 🙄
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May 12, 2005 at 6:49 pm #22430
biostudent84
Participantquote Poison:As much as I know, sickle cell anemia is a mutation. A person with sickle cell anemia has the tirplet GTG instead of GAG in the gene for hemoglobin. This base situation causes a valine to replace a glutamic acid in the hemoglobin. So…. Why don’t we call this a mutation? 🙄If I inherit a mutated gene from my father, then it is not a mutation in my body. The sequence of DNA that causes sickle-cell anemia can either be a mutation, or on an inherited allele.
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May 12, 2005 at 6:51 pm #22431
Jelanen
ParticipantThats what I’ve been trying to say, but haven’t seem to been able to put it that clear. Thanks.
-Jelanen
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May 12, 2005 at 7:37 pm #22434
MrMistery
Participant“Benefical and neutral mutations are transmitted to descendents”- Alberts textbook
So, when does a mutation stop being a mutation? F1? F2? -
May 12, 2005 at 7:39 pm #22436
canalon
Participantquote Jelanen:Thats what I’ve been trying to say, but haven’t seem to been able to put it that clear. Thanks.-Jelanen
OK, sorry for this misunderstanding. 😳
But what I wanted to say is that SCA is the product of a mutation that has been succesfully selected for.
But even in the first generation, the mutation GAG->GTG is still codominant, hence not recessive! So beside this problem of the definition of the term “mutation” what I was saying still holds true. 8) -
May 12, 2005 at 7:58 pm #22441
biostudent84
Participantquote MrMistery:“Benefical and neutral mutations are transmitted to descendents”- Alberts textbook
So, when does a mutation stop being a mutation? F1? F2?Look at genetic diseases. They had to come from some mutation somewhere along the line. I think Alberts made an absolute statement…an no-no in biology. It happens though…
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May 15, 2005 at 11:36 am #22523
victor
ParticipantYeah..I think about the same also. Sickle cell anemia is a mutation that happen on one of the organic bases so it produces wrong protein which is Valine instead of Glutamic acid..
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May 15, 2005 at 11:46 am #22524
victor
ParticipantI think for this sickle cell anemia case is mutation because the first condition that happen is a misreplication of organic bases then it lead to the misreplication of protein. So, this case is mutation..anyway, if this illness is inherited to the nect generation it’s not called an inherited allele illness because the first problem that happened is mutation..What do you think of that?
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May 15, 2005 at 2:06 pm #22530
Poison
Participantwhen it is inherited, yes, it isn’t a mutation in your body, but the starting of it is a mutation. And the books I looked name it as a mutation too.
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May 15, 2005 at 5:48 pm #22545
MrMistery
ParticipantMine also ozge…
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