[CJ_W]

So. . .this thread isn't about man/female stuff or money, or whatever but its a question that I figure someone here may have the answer to(there's a lot of smart people on this site)

So I was looking at something on down's syndrome, and how its pretty much due to some extra chromosomes or something. This causes the impairment etc etc. . .

So I was wondering . . .why isn't there something that is the OPPOSITE of that? like, an extra chromosome that gives someone like super smarts, strength, sight, pheromones or whatever.

I know this is kinda of a strange question, but I'm pretty sure someone smart lurks the forums here and could answer.

Just something I've been wondering heh.

[Sonsowey]

It's a bit like asking:

I know that cancer can be caused from nuclear radiation, etc.

But why doesn't nuclear radiation ever do the opposite, y'know, give you super strength, speed, lazer vision, etc.

[CJ_W]

(08-14-2013 09:54 PM)Sonsowey Wrote:  

It's a bit like asking:

I know that cancer can be caused from nuclear radiation, etc.

But why doesn't nuclear radiation ever do the opposite, y'know, give you super strength, speed, lazer vision, etc.

huh? No its not? I mean Radiation is a poison right? and down's syndrome comes from a genetic mutation right? so should't it make sense that maybe there could be a genetic mutation that would have some really GOOD effects?

[Wadsworth]

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Think of it as being a massive industrial chemical plant with hundreds of pieces of equipment involved. If you remove even one piece of equipment, probably the whole process shuts down. A random change in an industrial chemical plant like that might cause a favorable effect, but it's been designed to operate a certain way. The more likely scenario would be cascade failure.

[CJ_W]

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Ahh I see. That's interesting! Makes more sense to me.

[gringochileno]

Chromosomes have thousands of genes on them. When you duplicate an entire chromosome's worth of genes, a ton of proteins and metabolic pathways get thrown out of whack all at once, and the vast majority of these changes will be harmful, outweighing whatever small minority of the changes that might be beneficial. This is actually one of the main ways that evolution works - almost all gene mutations are harmful, but occasionally a helpful one will come along and be preserved by natural selection. That works when you're introducing novel mutations at a rate of 1 or 2 per generation--a small enough number to occasionally generate individuals with beneficial mutations who don't also have deleterious ones--but when you start duplicating thousands of genes at once at the chromosome level, the net effect is going to be very harmful.

[Caveman]

During the evolution of a species the number of chromosomes also changes due to some random mutation.

But these beneficial random mutations that change the species for the better happen very rarely, and for every one mutation that brings positive character traits there are like a million mutations that bring negative ones.

[gringochileno]

(08-14-2013 10:13 PM)Caveman Wrote:  

During the evolution of a species the number of chromosomes also changes due to some random mutation.

But these beneficial random mutations that change the species for the better happen very rarely, and for every one mutation that brings positive character traits there are like a million mutations that bring negative ones.

Yeah but even when chromosome numbers change, the number of genes will typically stay the same. It's extremely hard to imagine a scenario where duplicating thousands of genes at once would be beneficial to the organism, for the exact reason you state: almost all of the duplications would be harmful.

[La Familia]

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

[T and A Man]

Being born with a "Y" chromosone makes you smarter, stronger, faster and bigger.

You are definaely superior being born with a"Y" chromosone than not.

[CJ_W]

Damn, thanks for all the info, I learned a lot, especially from what gringochileno posted.

Maybe Roosh should open his own university.

Roosh V U

[Wadsworth]

(08-14-2013 10:21 PM)La Familia Wrote:  

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

[gringochileno]

(08-14-2013 10:28 PM)Wadsworth Wrote:  

(08-14-2013 10:21 PM)La Familia Wrote:  

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

I thought a silent mutation was one that doesn't alter the amino acid sequence of the protein the gene codes for due to redundancy in the genetic code. If that's the case, then why would a silent mutation in a highly conserved gene be selected against? (I'm genuinely curious; I'm not a geneticist and I very well may be missing something).

[Wadsworth]

(08-14-2013 10:33 PM)gringochileno Wrote:  

(08-14-2013 10:28 PM)Wadsworth Wrote:  

(08-14-2013 10:21 PM)La Familia Wrote:  

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

I thought a silent mutation was one that doesn't alter the amino acid sequence of the protein the gene codes for due to redundancy in the genetic code. If that's the case, then why would a silent mutation in a highly conserved gene be selected against? (I'm genuinely curious; I'm not a geneticist and I very well may be missing something).

Yeah, the amino acid sequence of a protein is coded into the genetic sequence on a chromosomal gene. The sequence of DNA between genes is massive, and mutations often happen in those areas. If, for example, a mutation occurred in the gene for the androgen receptor, then the androgen receptor protein would very likely have an inappropriate amino acid residue somewhere in the sequence. The protein wouldn't fold properly, and it's activity would plummet. The phenotype of the organism would likely be massively different if even it survived (I don't think androgen receptor knockouts are viable).

You can get a silent mutation in a gene that won't change the amino acid residue, because lets say ACC and ACG both code for the same amino acid. Generally speaking, though, most silent mutations don't occur in coding regions.

[Kabal]

(08-14-2013 10:13 PM)Caveman Wrote:  

During the evolution of a species the number of chromosomes also changes due to some random mutation.

But these beneficial random mutations that change the species for the better happen very rarely, and for every one mutation that brings positive character traits there are like a million mutations that bring negative ones.

This is a good rule of thumb.

Evolution finds local optimums, both in a mathematical and geographical sense.

Thus, any random deviances (mutations) will be much more likely to be deleterious than beneficial.

However, random positive mutations can indeed sweep through a human population very quickly.

Much more quickly than laymen, even ones cursorily familiar with evolutionary concepts, might realize.

In The 10,000 Year Explosion, Cochran and Harpending note that a 7% initial selective advantage could result in most of a population having that trait after 6,000 years (page 135), in reflecting upon the ApoA-IM mutation, which went from 1 copy to 43 in ten generations in Italy.

[La Familia]

(08-14-2013 10:28 PM)Wadsworth Wrote:  

(08-14-2013 10:21 PM)La Familia Wrote:  

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

Highly conserved gene sequences are slow evolving and less prone to mutations for the reasons you've mentioned. In this case, my point was made for the sake of clarification. As gringochileno stated, you can have silent mutations--such as a mutation that changes the structure of a protein by one amino acid (leucine instead of isoleucine, for example), yet the function remains unchanged. In this instance, you cannot see a physical change (unless we look at X-Ray crystallography), even though a minute change has occurred.

[Wadsworth]

(08-14-2013 10:42 PM)La Familia Wrote:  

(08-14-2013 10:28 PM)Wadsworth Wrote:  

(08-14-2013 10:21 PM)La Familia Wrote:  

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

Highly conserved gene sequences are slow evolving and less prone to mutations for the reasons you've mentioned. In this case, my point was made for the sake of clarification. As gringochileno stated, you can have silent mutations--such as a mutation that changes the structure of a protein by one amino acid (leucine instead of isoleucine, for example), yet the function remains unchanged. In this instance, you cannot see a physical change (unless we look at X-Ray crystallography), even though a minute change has occurred.

Ah, you're right, that counts as a silent mutation too.

[gringochileno]

(08-14-2013 10:38 PM)Wadsworth Wrote:  

(08-14-2013 10:33 PM)gringochileno Wrote:  

(08-14-2013 10:28 PM)Wadsworth Wrote:  

(08-14-2013 10:21 PM)La Familia Wrote:  

(08-14-2013 10:05 PM)Wadsworth Wrote:  

It's theoretically possible I suppose. Altered genotypes do cause altered phenotypes. But normally the most minute change in genotype produces massive changes in phenotype. Normal physiology and biology exists within a pretty narrow range, because I suppose one way of looking at it is just as one massive chemical reaction. If you change the conditions of the reaction, the most likely scenario would be a hugely deleterious effect.

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

I thought a silent mutation was one that doesn't alter the amino acid sequence of the protein the gene codes for due to redundancy in the genetic code. If that's the case, then why would a silent mutation in a highly conserved gene be selected against? (I'm genuinely curious; I'm not a geneticist and I very well may be missing something).

Yeah, the amino acid sequence of a protein is coded into the genetic sequence on a chromosomal gene. The sequence of DNA between genes is massive, and mutations often happen in those areas. If, for example, a mutation occurred in the gene for the androgen receptor, then the androgen receptor protein would very likely have an inappropriate amino acid residue somewhere in the sequence. The protein wouldn't fold properly, and it's activity would plummet. The phenotype of the organism would likely be massively different if even it survived (I don't think androgen receptor knockouts are viable).

You can get a silent mutation in a gene that won't change the amino acid residue, because lets say ACC and ACG both code for the same amino acid. Generally speaking, though, most silent mutations don't occur in coding regions.

Okay I follow you here. I think we have a terminological difference--I always understood the term "silent mutation" as referring specifically to a nucleotide-level change in a functional gene that doesn't alter the amino acid sequence of the resulting protein. You seem to also be including mutations that occur in non-coding regions. Maybe I was mistaken about this definition.

I agree that a point mutation changing a single amino acid in an essential gene is often completely devastating. Sickle Cell Disease and Cystic Fibrosis are classic examples of this. Even here, though, the exact amino acid that's changed seems to matter crucially--there are specific residues in the B-globin and chloride channel proteins that appear to be particularly well-conserved and liable to cause disease if they're mutated, while other regions of the proteins seems to be much more forgiving of changes to the amino acid sequence. It likely has something to do with needing certain parts of the sequence to have a certain charge in order for the protein to fold properly.

As an aside, people without functioning androgen receptors are viable, in fact knocking out the androgen receptor results in a very interesting disease!

[Wadsworth]

(08-14-2013 10:54 PM)gringochileno Wrote:  

(08-14-2013 10:38 PM)Wadsworth Wrote:  

(08-14-2013 10:33 PM)gringochileno Wrote:  

(08-14-2013 10:28 PM)Wadsworth Wrote:  

(08-14-2013 10:21 PM)La Familia Wrote:  

Not always true; if that were the case, then all of our silent mutations would be visibly evident and therefore, not silent.

One answer to your question is that in order for one to obtain super human abilities, the mutations must be beneficial. On average, most mutations in our DNA are neutral or deleterious. Additionally, you have to consider the increased energy cost required to maintain those improved traits, and that is dependent on factors such as the availability of resources in your environment or the rate of ATP production.

It's fun to think in what ways we can evolve to become more biologically efficient humans. Too bad we will most likely be exterminated before we can evolve and inherit perceived super powers.

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

I thought a silent mutation was one that doesn't alter the amino acid sequence of the protein the gene codes for due to redundancy in the genetic code. If that's the case, then why would a silent mutation in a highly conserved gene be selected against? (I'm genuinely curious; I'm not a geneticist and I very well may be missing something).

Yeah, the amino acid sequence of a protein is coded into the genetic sequence on a chromosomal gene. The sequence of DNA between genes is massive, and mutations often happen in those areas. If, for example, a mutation occurred in the gene for the androgen receptor, then the androgen receptor protein would very likely have an inappropriate amino acid residue somewhere in the sequence. The protein wouldn't fold properly, and it's activity would plummet. The phenotype of the organism would likely be massively different if even it survived (I don't think androgen receptor knockouts are viable).

You can get a silent mutation in a gene that won't change the amino acid residue, because lets say ACC and ACG both code for the same amino acid. Generally speaking, though, most silent mutations don't occur in coding regions.

Okay I follow you here. I think we have a terminological difference--I always understood the term "silent mutation" as referring specifically to a nucleotide-level change in a functional gene that doesn't alter the amino acid sequence of the resulting protein. You seem to also be including mutations that occur in non-coding regions. Maybe I was mistaken about this definition.

I agree that a point mutation changing a single amino acid in an essential gene is often completely devastating. Sickle Cell Disease and Cystic Fibrosis are classic examples of this. Even here, though, the exact amino acid that's changed seems to matter crucially--there are specific residues in the B-globin and chloride channel proteins that appear to be particularly well-conserved and liable to cause disease if they're mutated, while other regions of the proteins seems to be much more forgiving of changes to the amino acid sequence. It likely has something to do with needing certain parts of the sequence to have a certain charge in order for the protein to fold properly.

As an aside, people without functioning androgen receptors are viable, in fact knocking out the androgen receptor results in a very interesting disease!

Yeah, I remember reading about the sickle cell example, very interesting. That's really interesting about the androgen receptor. I know they've studied estrogen receptor alpha and beta knockouts extensively.

Hm, thanks very much for clarifying guys, I'd forgotten a key component of silent mutations.

[WesternCancer]

I've been out of school 3 months and I've already forgotten everything... fuck.

To answer the OP: that kind of stuff happens pretty frequently in plants. Something will fuck up in reproduction and instead of having 2 sets of every chromosome it'll have 3 or something. Its believed that during mass extinction events stuff that has the most of something like a gene or even a chromosome duplication will be most likely to survive the event.

That being said I don't know exactly why it is not possible in humans. I would assume its because humans are much more complex than something like a plant. Altering one amino acid in one gene to something that has a slightly smaller side chain can fuck you up so bad you will get a disease and won't make it to your 5th birthday.

Silent mutations: even though silent mutations don't produce a noticable phenotype there is a difference between organisms in their G/C A/T contents as well as tRNAs. tRNAs aren't present in equal amounts so if you have a silent mutation and it uses a different tRNA to get the same amino acid it will have a higher 'evolutionary cost' and will be deleterious (but nearly unnoticable)

As for conserved sequences: they undergo a much lower rate of mutation because they are essential. Everything is fucked if you have even a slight change in the sequence. eg. histones (help in DNA coiling. DNA + Proteins = chromatin). if the sequence is changed so that the aa side chain is even one carbon less it will mess everything up and have disastrous results.


^^^ to the above
the sequence of amino acids is extremely important in the funcational part of a protein (ie. active sites of enzymes, protein channels). It is often specific down to a certain residue. a Histidine at aa 144 could create the necessary chemical and physical properties for an enzymes substrate to bind. Change that to a leucine at position 144 and you're screwed.

[La Familia]

(08-14-2013 10:58 PM)Wadsworth Wrote:  

(08-14-2013 10:54 PM)gringochileno Wrote:  

(08-14-2013 10:38 PM)Wadsworth Wrote:  

(08-14-2013 10:33 PM)gringochileno Wrote:  

(08-14-2013 10:28 PM)Wadsworth Wrote:  

Silent mutations don't occur on highly evolutionarily conserved genes. They normally occur in DNA stretches between genes. Alot of that DNA is malleable, and often contains viral DNA. If a highly conserved gene were mutated, the fitness of that organism would almost certainly tank and the gene would be selected against. Most mutations to genes aren't silent, they change the phenotype significantly.

I thought a silent mutation was one that doesn't alter the amino acid sequence of the protein the gene codes for due to redundancy in the genetic code. If that's the case, then why would a silent mutation in a highly conserved gene be selected against? (I'm genuinely curious; I'm not a geneticist and I very well may be missing something).

Yeah, the amino acid sequence of a protein is coded into the genetic sequence on a chromosomal gene. The sequence of DNA between genes is massive, and mutations often happen in those areas. If, for example, a mutation occurred in the gene for the androgen receptor, then the androgen receptor protein would very likely have an inappropriate amino acid residue somewhere in the sequence. The protein wouldn't fold properly, and it's activity would plummet. The phenotype of the organism would likely be massively different if even it survived (I don't think androgen receptor knockouts are viable).

You can get a silent mutation in a gene that won't change the amino acid residue, because lets say ACC and ACG both code for the same amino acid. Generally speaking, though, most silent mutations don't occur in coding regions.

Okay I follow you here. I think we have a terminological difference--I always understood the term "silent mutation" as referring specifically to a nucleotide-level change in a functional gene that doesn't alter the amino acid sequence of the resulting protein. You seem to also be including mutations that occur in non-coding regions. Maybe I was mistaken about this definition.

I agree that a point mutation changing a single amino acid in an essential gene is often completely devastating. Sickle Cell Disease and Cystic Fibrosis are classic examples of this. Even here, though, the exact amino acid that's changed seems to matter crucially--there are specific residues in the B-globin and chloride channel proteins that appear to be particularly well-conserved and liable to cause disease if they're mutated, while other regions of the proteins seems to be much more forgiving of changes to the amino acid sequence. It likely has something to do with needing certain parts of the sequence to have a certain charge in order for the protein to fold properly.

As an aside, people without functioning androgen receptors are viable, in fact knocking out the androgen receptor results in a very interesting disease!

Yeah, I remember reading about the sickle cell example, very interesting. That's really interesting about the androgen receptor. I know they've studied estrogen receptor knockouts alpha and beta knockouts extensively.

Hm, thanks very much for clarifying guys, I'd forgotten a key component of silent mutations.

Yeah, I remember that sickle cell example too. Along with the Hox example with the bee that grew a leg out of its head. It's good to see RVFers with genetic and molecular biology backgrounds!

[WesternCancer]

Yeah man Hox genes are nuts. They're highly conserved and determine anterior/posterior positioning of body parts. They're activated by various proteins/hormones. To much of one and you're going to grow a head where your ass should be.

[Wadsworth]

(08-14-2013 11:14 PM)WesternCancer Wrote:  

Yeah man Hox genes are nuts. They're highly conserved and determine anterior/posterior positioning of body parts. They're activated by various proteins/hormones. To much of one and you're going to grow a head where your ass should be.

The feminist would look at that and call it a social construct.

[Thomas the Rhymer]

(08-14-2013 09:50 PM)CJ_W Wrote:  

So. . .this thread isn't about man/female stuff or money, or whatever but its a question that I figure someone here may have the answer to(there's a lot of smart people on this site)

So I was looking at something on down's syndrome, and how its pretty much due to some extra chromosomes or something. This causes the impairment etc etc. . .

So I was wondering . . .why isn't there something that is the OPPOSITE of that? like, an extra chromosome that gives someone like super smarts, strength, sight, pheromones or whatever.

I know this is kinda of a strange question, but I'm pretty sure someone smart lurks the forums here and could answer.

Just something I've been wondering heh.

Well, sometimes an extra gene pops in or some gene is deleted and people do develop super powers. They are unusually flexible, or have unusually good vision, or have unusually powerful memories, or are unusually successful getting laid...

An example: So say you either get an extra gene for muscle production or you've lost the gene for myostatin production (which inhibits muscle growth), then you develop super strength. A few humans have been born with such super strength.

This 'super muscle' condition also on occasion occurs in dogs...


BTW, that's not a pit bull, that's a super-muscled whippet...

Normal looking whippet:

[Huck Finn]

Humans do not tolerate variation in chromosome number well. We have 23 pairs of chromosomes, 1 pair is our sex chromosomes, XY for men, XX for women. We have 22 pairs of autosomes. If a embryo is missing an autosome, it will terminate, humans cannot be monosomic(45 chromosomes resulting in one autosome missing), variation in sex chromosome number is often less severe and may lead to a "viable" fetus. Trisomy 21 is the most common form of down syndrome and it occurs from when instead of having 2xchromosome 21(autosome), the individual has 3xchromosome 21. Gene dosage is the reason problems are caused by the extra 21 chromosome, we are finely balanced biological machines, when things are thrown out of joint, there are many flow on effects, essentially chromosome variation is always very bad.