Is true identical cloning even possible?

[GWestphal]

I understand the genetics would be the same, but could you make a real 100% identical clone. It seems that gene expression is regulated by the milieu of supporting molecules present from conception onward. Since we wouldn't know the exact gradients and concentrations, we wouldn't be able to get the exact same result as the donor of the DNA. Is that right? Now each clone if created under the same circumstances would be identical, but just not identical to the donor.

 

[Fayd]

I understand the genetics would be the same, but could you make a real 100% identical clone. It seems that gene expression is regulated by the milieu of supporting molecules present from conception onward. Since we wouldn't know the exact gradients and concentrations, we wouldn't be able to get the exact same result as the donor of the DNA. Is that right? Now each clone if created under the same circumstances would be identical, but just not identical to the donor.

not really, no. every stage of the process introduces the potential for mutation.

 

[TecHNooB]

not really, no. every stage of the process introduces the potential for mutation.

I coulda sworn you had more posts than that.

 

[Fayd]

I coulda sworn you had more posts than that.

i lost everything in the transition.

i never bothered asking the moderators to fix the account.

my name was also capitalized back then.

 

[Gibsons]

I understand the genetics would be the same, but could you make a real 100% identical clone. It seems that gene expression is regulated by the milieu of supporting molecules present from conception onward. Since we wouldn't know the exact gradients and concentrations, we wouldn't be able to get the exact same result as the donor of the DNA. Is that right? Now each clone if created under the same circumstances would be identical, but just not identical to the donor.

You've got a perfect case study in identical twins. Identical twins aren't really completely identical, people close to them can tell them apart, sometimes just by voice. Fingerprints are usually (always?) different too.

To put it in a more highly technical vein, development involves many non-linear processes.

 

[MStele]

Probability theory throws a wrench in the metaphorical machine. Nothing can be truly cloned in a identical sense, because no system can be isolated enough to eliminate variation. The real question is, how close is close enough to be declared a clone?

Its possible to clone something to a degree that cosmetically it is nearly indistinquishable from the donor, but that is merely a perception. There are always variations. There is always a bit of randomness to biology that makes it more of an interpretative science than a definitive one. Sure, correlation can be verified and calculations can be made, but on a microscopic level things are far less predictable than they are on a macroscopic level.

 

[dkozloski]

This is the big sticker in the idea of eliminating genetic diseases by a process of eugenics. Just about the time you think you have won, the same problem crops up again through a spontaneous mutation.

 

[BarkingGhostar]

Even if you clone the genome exactly the expression of those genes (aka epigenome) is something totally different.

 

[Shadow Conception]

Probability theory throws a wrench in the metaphorical machine. Nothing can be truly cloned in a identical sense, because no system can be isolated enough to eliminate variation. The real question is, how close is close enough to be declared a clone?

Its possible to clone something to a degree that cosmetically it is nearly indistinquishable from the donor, but that is merely a perception. There are always variations. There is always a bit of randomness to biology that makes it more of an interpretative science than a definitive one. Sure, correlation can be verified and calculations can be made, but on a microscopic level things are far less predictable than they are on a macroscopic level.

Are things random on a microscopic level? Or just not understood by humans yet?

 

[exdeath]

Are things random on a microscopic level? Or just not understood by humans yet?

Random.

You can use the same genetic starting point, but you can't control the micro scale processes that go on autonomously like cells dividing, external environmental conditions, diet, etc. If we could control things like that we could eliminate cancer among other things.

It's kind of like how no two CPUs or no two engines for a car are alike even when they come off the same assembly line back to back, using the same metal from the same batch from the same manufacturer, using the same castings; still going to have random variations since each grain of metal (or silicon) 'behaves' on it's own.

Or similar to nuclear processes like U-235 splitting; it's random and completely spontaneous and unpredictable. In nature you are dealing with probabilities.

And that's just the physical part; obviously the mental side of it, brain neural network creation, personality, etc, are 100% products of environment.

 

[Shadow Conception]

Couldn't you use that randomness to create true random generators, then? Instead of the pseudorandom generators we learned about in AP comp sci?

And how do we really know that there's not some underlying pattern to the supposed randomness? If you graph a function with many curves, and only graph points spaced apart very wide, would the pattern not look random only because we didn't know it was a graph of a certain function?

 

[WalkerDPlank]

One thing is true, is that at the time of this post true identical cloning is not possible, but neither is sending a man to pluto. I do believe science in the future could solve both.

 

[MStele]

One thing is true, is that at the time of this post true identical cloning is not possible, but neither is sending a man to pluto. I do believe science in the future could solve both.

Sending a man to pluto is easy. The trick is getting him their alive. The hardest part about space travel is biology. It's a matter of acceleration costs. The human frame can only take so many g forces, which translates into a slower cruise velocities, which translates into excessive travel time. As far as the engineering, its just a matter of scale. Unless faster-than-light travel moves from theory to practicality, going to Pluto will likely never be an option as a travel destination for humans.

True identical cloning is not possible, but not because the science hasn't found a way. It's because current understanding physics forbids it. In physical systems with many constituents there is a natural evolution toward greater disorder, since disorder can be a achieved in many more ways than order. This means that physical systems tend to evolve toward states of higher entropy. As an organism grows, there are various tiny variations that manifest in its various components. We can't create a truly identical copy of anything in manufacturing, and thats where we have the most control. In biology, we have even less control.

 

[KIAman]

You mean nobody learned anything from the movie "The Island?"

 

[jimhsu]

Genetically yes, there is a finite (though relatively small) probability that the clone has identical DNA to the original. Given a mutation rate of 2.5x10^-8, the probability of this occurring is somewhere around 2.67863696 × 10^-33 (assuming the Poisson distribution). If you count human mtDNA into this (mutation rate 3×10^-6), it is even less likely: 9000^0*e^-9000/0! or basically zero. Then again, 99% of your genome is junk DNA anyways, and point mutations in intron regions generally (but not always) don't matter. The point is you can fudge the numbers in a lot of ways.

In actuality, almost certainly no. Environmental variations determine a huge number of possible morphological traits.

 

[wwswimming]

I understand the genetics would be the same, but could you make a real 100% identical clone. It seems that gene expression is regulated by the milieu of supporting molecules present from conception onward. Since we wouldn't know the exact gradients and concentrations, we wouldn't be able to get the exact same result as the donor of the DNA. Is that right? Now each clone if created under the same circumstances would be identical, but just not identical to the donor.

are you asking about animal cloning, or also about plant cloning ?

i've been scolded a few times by other gardeners for growing apples from seed. they say i have to buy a cloned one, that i'll "just get mushy apples".

anyway, plant cloning is very common in agriculture. i don't know if the clones are completely identical. if you buy 2 "Pacific Rose" baby apple trees from a nursery, trees which used the same parent for the cloned branches, will they be 100% identical or just 99% identical ?

 

[Gibsons]

are you asking about animal cloning, or also about plant cloning ?

i've been scolded a few times by other gardeners for growing apples from seed. they say i have to buy a cloned one, that i'll "just get mushy apples".

anyway, plant cloning is very common in agriculture. i don't know if the clones are completely identical. if you buy 2 "Pacific Rose" baby apple trees from a nursery, trees which used the same parent for the cloned branches, will they be 100% identical or just 99% identical ?

The numbers jimhsu provided for humans are probably ballpark close for plants. If you look really really hard (ie sequence the genomes), you can find differences in DNA sequences. Most of them will make no difference in phenotype though.

 

[MStele]

As I posted earlier, I think there a distinction between cosmetic versus actual. I believe that its much easier to create a "clone" that is percieved as identical versus being identical, since even with a perfectly cloned genome biological variation is inevitable. These variations might be so minute that they don't alter that overall makeup of the organism, but their existance directly contradicts the ability to form an identical clone. So the real question is, how close does a copy have to conform to the original organism in order to count as a clone?

 

[MalVeauX]

I understand the genetics would be the same, but could you make a real 100% identical clone. It seems that gene expression is regulated by the milieu of supporting molecules present from conception onward. Since we wouldn't know the exact gradients and concentrations, we wouldn't be able to get the exact same result as the donor of the DNA. Is that right? Now each clone if created under the same circumstances would be identical, but just not identical to the donor.

No.

If a Human and an Ape are in the 95% genetic similarity range. A perfect clone would being at best, probably about 99%. Never 100%. You can't have a 100% clone of something that is living that has ribosomes and reproduces via mitosis.

The simple reason being, the moment they split, they are genetically identical for a time. But as they form into two bodies, mature, get born, etc, they're genetically different even though they're still incredibly similar. But slight mutation occurs with all division. So it's impossible to have a 100% copy of someone. You can have a 99.9999999999999999999999999999% copy of someone, but not 100%. You can't copy the mutations that are random, and that starts and continues (and mutates even more over the life span due to various exposures, age, etc) all through their life.

Very best,

 

[nismotigerwvu]

Don't forget about mitochondrial DNA. Current cloning methods result in mtDNA of the egg donor.

 

[jimhsu]

The numbers jimhsu provided for humans are probably ballpark close for plants. If you look really really hard (ie sequence the genomes), you can find differences in DNA sequences. Most of them will make no difference in phenotype though.

Also keep in mind error rates for sequencing are fairly high (sometimes even up to 10^-3). This seems to be inversely proportional to read lengths (ie Illumina platforms have much shorter read lengths than Sanger sequencing) - I need to find a reference for this though. This is why practically all sequencing techniques utilize multiple coverage (i.e. 5X or 10X, which indicate the number of total sequenced base pairs divided over the length of the genome) - so basically sequencing can be arbitrarily accurate given that you have enough money and patience.

PS Illumina released full genome sequencing June 2009 at 30X coverage for $48000. http://www.everygenome.com/ 5 MONTHS later, Complete Genomics announced sequencing at $1700. The extent to which sequencing advances pwn Moore's Law is ... astounding (hence the "drowning in data" analogy that a lot of scientists in the field use: see http://www.guardian.co.uk/technology/2008/feb/28/research.computing ). The race is on for the magical $1K number (which will be when most people at birth get their genomes sequenced)...