The genetic theory of channeling

[Achoo]

It has long been known that the ability to channel has a genetic component. After reflection, I have come up with a theory on the heredity of channeling abilities which seems to fit with most facts

 

There are three possible alleles that determine a person's ability to channel: the normal allele, the saidin allele and the saidar allele. These three alleles have an order of dominance: the normal allele is dominant to both others, the saidin allele is recessive to the normal allele but dominant to the saidar allele and the saidar allele is recessive to both others.

The normal allele can be found on either sex chromosome, the saidin allele on only the Y chromosome and the saidar allele only on the X chromosome. Since the sex chromosomes don't participate in crossing-over(an exchange of genes with the complementary chromosomes), these genes never switch chromosomes.

 

To channel, a woman needs two saidar alleles, since a normal allele would suppress a single saidar allele. Similarily, a man who channels can not have a normal allele, since this would suppress his ability to channel; he needs a saidin allele on his Y chromosome and a saidar on his X.

 

Since channelers possess only channeling alleles, any child of two channelers will be able to channel. The children of a female carrier(only one saidar allele) and a male channeler have a 50-50 chance of being able to channel. The sons of any man carrying only the saidin allele and a channeling woman will channel, but none of the daughters of that same couple will have the ability. On the other hand, a man carrying only the saidar allele and a channeling woman will have daughters that can channel, but no sons with the ability(although these latter will carry the saidar allele from their mother). If two carriers have children, the odds that their children will channel depend on the allele carried by the father. If the father carries the saidin allele, his sons will have a 1 in 2 chance of channeling, if he carries the saidar allele, his daughters have a 1 in 2 chance of channeling. In either case, the children that are the right gender to channel, but can't, will be carriers.

Because both channeling alleles are recessive to the normal allele, any union involving a partner with two normal alleles will produce no channelers. In any union with one parent that does channel and one who does not even carry the alleles for it, the children will all be carriers. In fact, anytime a channeling parent has offspring, that child will be either a carriers or a channeler.

 

The recessiveness of the channeling alleles also explains how non-channeling parents are able to have channeling children.

 

Although the gene which determines whether or not one is able to channel are on the sex chromosomes, the genes which determine potential are not.  Potential in the One Power is a polygenic trait, meaning that there are many different genes (17 in this case) which determine one's maximum potential either in saidin or in saidar. The genes to determine strength are located on the fourth (2 genes), ninth (6 genes) and sixteenth (9 genes) chromosomes. All people, channelers or not, possess these genes, although in non-channelers they have not observable effect. The 17 different genes affect one's potential in the Power with different magnitudes in such a way that no two different combinations will produce the same potential. Each gene can be either ON(adding to a channeler's ability or OFF(not adding to the channeler's ability), so there are 2 to the 17, or 131, 072, possible strengths. Of the 17 genes, 7 have dominant ON alleles and 10 have recessive ON alleles.

 

It is very rare that someone has maximum potential, since there are 131, 071 other possible strengths and since some of the ON alleles are quite rare. It has been theorized that Lews Therin and his reincarnation Rand Al'Thor (as well as other unknown champions of the Light) had maximum potential, since there has never been stronger. If so, this incredible chance is probably due to the weaving of the Wheel, which likely manipulates the reproduction of mankind to create as strong as possible a channeler to be the Dragon Reborn.

 

After a channeler reaches a certain potential, they may have the ability to touch the Power on their own, but there are also psychological factors to this spark.

 

In the eastern continent, powerful female channelers have been taken into the White Tower and groomed to be Aes Sedai, who don't have children, or touched the Source on their own, often killing themselves. It is only wilders, women and men who did not have the psychological factors necessary to touch the source on their own and women and men who cannot channel who have passed on the genes for enormous power in the Power, and strong channelers there are rare. Most strong channelers come from the Aiel (Wise Ones often have children), the Sea Folk (similar situation to that of the Aiel), the Seanchan (where channeling women probably had children until Hawking's armies started leashing them 1000 years ago) or in regions mostly ignored by the Aes Sedai (ex. the Two Rivers). Even in these areas, however, strong channelers and channelers in general are less common than in the Age of Legends because male channelers go insane and die before passing on either the saidar gene or the genes contributing to strength in the Power. It does not help that there are many factions glad to kill anyone who channels.

[mb]

Interesting theory, but any gene is determined by just two alleles; the mother's allele and the father's allele.

It seems saidar and saidin would be the same thing genetically.

 

This page talks some about channeling & genetics:

http://www.wotmania.com/faqtopic.asp?ID=38

 

[Roxinos]

You're right that saidin and saidar would each be an allele for channeling, but you're wrong that any gene is only determined by two alleles. Any person can have more than one recessive gene which determines any given attribute. (Which is a bit of an oversimplification on what the gene is.) As such, there can be many alleles.

[Achoo]

...any gene is determined by just two alleles; the mother's allele and the father's allele.

 

Although each person has only two alleles (one from each parent), many different alleles for any given trait may exist. Take, for example, the gene to determine blood types. There are three alleles for blood type in humans: the codominant A and B alleles and the recessive O allele. The real problem in the theory is the order of dominance, a phenonmenon not observed anywhere. However, genetics is still a young field and what causes dominance and recessiveness is still unknown, so it is not impossible.

 

Also, thank you for the link. I find it most interesting.

[Thorum]

There is some confusion in terms here: a person can have multiple pairs of alleles for the same trait (this is even the most common base). An allel is just one possible combination for one gen. It's better to speak of the number of genes.

 

Now, on to some remarks on the theory:

 

1) You assume there is a Saidin/Saidar/none gene on the X/Y chromosome. This looks very likely because there are far fewer men channeling than women (with very little saidin-alleles). However, to me it seems more likely that there is more than one gene, of which only one is obligatory on the X/Y chromosome.

Why?

- Because the chance your children can channel if you can has to be much smaller, and can arise too much in unsuspected persons (why would they have such a thorough channeling search system in the AOL if it as genetic as in your example?)

- Aes Sedai would have becoming much more extinct then they are, or there had to be a LOT more than we know of in the beginning of the Third Age.

This is also why your last sentence is wrong:

Even in these areas, however, strong channelers and channelers in general are less common than in the Age of Legends because male channelers go insane and die before passing on either the saidar gene or the genes contributing to strength in the Power.

 

2) There could easily be a potentiality gene on the Y chromosome. This would immediately indicate why men are more often stronger in Saidin than women are in Saidar.

 

3) Why do you separate the potentiality genes that far? The total number, the chromosomes they are located on, the dominant/recessive ones, ... is all pure speculation, nothing more. You're also missing a couple of possibilities:

- not all genes have to ADD potential (the ability can be at least also multiplied, divided, substracted)

- there can be more than ON or OFF alleles. There can be a ON, a OFF, and a 17,85% ON allel (random number).

- due to genetics, the chromosome the genes are located on, the number of genes, and even their strength can differ from individual to individual.

- alleles don't have to be dominant/recessive. They can also work independently from each other.

 

4) Being the strongest possible, has all to do with LUCK. Which, coincidentaly, is the field in which the Wheel adjusts itself.

 

5) Psychological factors for the spark? While this could be possible an sich, I believe it is even more possible for the potential. The better you are trained, the more of your potential you develop. And, believe it or not, there is even a genetical factor in this (which is not transmitted to your children) - called histones (proteins which can block and unblock genes - read: potential).

The spark could much more easily be purely genetic. For example: 5 genes, of which 2 need a certain allel to have a spark borne into you.

 

 

The real problem in the theory is the order of dominance, a phenonmenon not observed anywhere.

 

What do you mean here? Alleles of certain genes can shut down or activate other genes. Which is a reason for dominance among genes. Among allels, dominance is quite very much observed...

 

what causes dominance and recessiveness is still unknown

 

Not true. Genes make proteins. The dominant allel is the one which is expressed in reality.

 

Fictive (but possible) examples - the second one is a hard one:

- There is a gene which produces the protein to open your nostrils. A is the working allel of the gene, B is a non-functional version (due to radiation, ...). A is dominant, because one gene can (almost?) always produce enough protein to induce the effect. This is even more certain with genes which are THAT important.

- There is a gene which procuces the protein to bind Calcium to your bones. C is the normal alle of the gene, D is a version which doesn't bind to the bone, E is a version which doesn't bind Calcium.

If you have C and E, the protein from E binds on the bones, so there is not enough place for the protein from C to bind. Also, the release of a protein like this is triggered by the binding of Calcium. Which means that after a while, there is nowhere left for C to bind. So, E is dominant (it blocks everything).

If you have C and D, D cannot do anything, so normal calcium-binding will take place. C is dominant.

Here, you have E > C > D. But not necessarily E > D ;D

[Thorum]

Oh yes, forgot one thing: I've finished my studies (biology - including a lot of genetics) in 2007. Some of the things I'm stating as truth here can have changed since then.

[Nightstrike]

The BWB says that channeling ability is a genetic recessive. I do not think there are different saidin/saidar alleles, since Aran'gar channels saidin. Instead I think we might have a situation where abilities are determined by a gene not located on any sex chromosome. There are probably other genes that influence sparking, maybe even modifying their strength in some way. We know that RJ said that a sparker in one lifetime does not have to be reborn as a sparker in the next. I think genetics are the cause for this. The more of the "resistance" genes they are born with, the harder it is to overcome the threshold for becoming a sparker. But the stronger the soul is, the more likely it is for them to succeed (despite their "bad genes"). That could explain the situation with Sharina, I believe.

 

From "Thus Spake the Creator":

"Is channeling ability strictly, or partly geneticaly based?" partially. Worked it a bit with some friends but just left it mostly hanging.  "Can weaves be inverted in a way that prevents them being detected even while they are being woven, ie so you could draw and weave with Saidin, and noone would detect it, or can the weaves only be hidden after they have been tied off?" no answer.

I think that might mean that he hadn't decided exactly how he wanted these things to work.

 

 

[vainebekonnes]

I always believed from his comments and the like that whether or not you could channel was dependent upon the body, but to what degree you could channel was mostly based upon the soul.  Certainly a really complex system of chromosomes could handle all of this genetically, but we are looking at three different stages of being able to channel or not, and 21 different levels of power.  I'm sure that's it's possible to determine mathematically what the minimum number of required chromosomes would be to get this effect, I'm just not knowledgeable enough in genetics to do it myself.  However, since RJ said that channeling is "partially" determined by genes, that means any number of unknowable variables we have to take into account.

[Achoo]

-vainebekonnes-

 

I've always believed from his comments and the like that whether or not you could channel was dependent upon the body, but to what degree you could channel was mostly based upon the soul

I've always believed that whether or not you can channel and what power you could hope to achieve were both genetic, sinc Aes Sedai always speak of potential as an unchanging maximum. However, I do agree that how much of your potential you can use is dependent on training ect. I am sorry if this was unclear.

 

-Nightstrike-

 

I do not think there are different saidin/saidar alleles, since Aran'gar channels saidin

 

Aran'gar's ability to channel likely has nothing to with the body into which he was placed; that body probably didn't have the ability to channel at all. It is far more likely that Aran'gar's soul and mind were able to access saidin simply because they already knew where to find it, in a manner of speaking.

 

We know that RJ said that a sparker in one lifetime does not have to be reborn as a sparker in the next. I think genetics are the cause for this. The more of the "resistance" genes they are born with, the harder it is to overcome the threshold for becoming a sparker. But the stronger the soul is, the more likely it is for them to succeed (despite their "bad genes").

 

Actually, this fits in well with both the facts as we know them and my theory. Good thinking.

 

-Thorum-

 

why would they have such a thorough channeling search system in the AOL if it as genetic as in your example?

 

An extensive search system would help in finding those channelers with hybrid parents(who wouldn't be able to channel) and children of parents whose channeling abilities were not previously discovered.

 

Aes Sedai would have becoming much more extinct then they are, or there had to be a LOT more than we know of in the beginning of the Third Age.

 

There would be a great number of carriers and channelers who don't spark to reproduce and keep the genes in the population even while other channelers aren't having children.

 

2) There could easily be a potentiality gene on the Y chromosome. This would immediately indicate why men are more often stronger in Saidin than women are in Saidar.

 

I thought of a gene (on an autosome) that would only contribute to male channelers to explain this, but decided not to include for fear of being accused of sexism. However, since you brought it up, I can now blame you for saying that male channelers are often better than female channelers ;).

 

Why do you separate the potentiality genes that far?

 

For fun.

 

You're also missing a couple of possibilities:

- not all genes have to ADD potential (the ability can be at least also multiplied, divided, substracted)

- there can be more than ON or OFF alleles. There can be a ON, a OFF, and a 17,85% ON allel (random number).

- due to genetics, the chromosome the genes are located on, the number of genes, and even their strength can differ from individual to individual.

- alleles don't have to be dominant/recessive. They can also work independently from each other.

 

I thought of some of these ideas (although not all), but decided to keep my post relatively simple and short. For example, I considered a gene that could contribute to male channelers or female channelers, but ended up leaving it out.

 

4) Being the strongest possible, has all to do with LUCK. Which, coincidentaly, is the field in which the Wheel adjusts itself.

 

That's what I was trying to say in that bit about Rand, Lews Therin and the Wheel, although in hindsight I wasn't very explicit. Also in hindsight, this is probably why so many powerful channelers are popping up around Tarmon Gai'don. It seems obvious, so I don't know why I didn't think of that earlier.

 

Quote

The real problem in the theory is the order of dominance, a phenonmenon not observed anywhere.

 

What do you mean here?

 

By "order of dominance", I meant the idea that an allele can be recessive to one and dominant to another, like the saidin allele. As far as I know, this has never been observed.

 

The spark could much more easily be purely genetic. For example: 5 genes, of which 2 need a certain allel to have a spark borne into you

 

This is possible, but I was thinking that somewhere where being a channeler is particularly frightening, as in Seanchan, one might develop a block like Nynaeve's before they even touched The Source.

 

Here, you have E > C > D

 

So the order of dominance is possible, eh? That's a relief. Thanks.

[mb]

...any gene is determined by just two alleles; the mother's allele and the father's allele.

 

Although each person has only two alleles (one from each parent), many different alleles for any given trait may exist. Take, for example, the gene to determine blood types. There are three alleles for blood type in humans: the codominant A and B alleles and the recessive O allele.

I forgot.

Some other example came to mind when I was logging off: hair color (black & brown being dominant, red & blond being recessive)

And another just now: skin tone (dark, medium, light; not sure which are dominant nor which are recessive)