Sansa does not have a wolf anymore and that may explain her lack of skinchanging. I would be a fool not to point out that Uncle Brandon and Lyanna spent a good deal of time riding horses and were called centaurs, suggesting they were linked to their horses. I can't say any animal Ned or Benjen spent time around in their childhood or adult life, but they may have had similar stories. Perhaps Ned didn't bond with any creature like his brother and sister, unless one of the oxen or ravens in the Eerie was special to him. Maybe skinchanging is more than genetic, perhaps external factors are needed. You need the underlying genes there, yes, but something else should be there before they can unlock skinchanging. Such as low grade/rate radiation poisoning acting on the gene, then trauma to unlock it properly.
If Cat is single X my bet is house Tully NOT being carriers of Skinchanging and Greenseeing. House Whent is heavily implied to be connected to Lothston which are more likely to be Skinchangers.
Klinefelter Syndrome has other phenotypical and mental markers which Bran doesn't exhibit. Also, a more typical example of a X Recessive Trait to explain that type of genetic heritage would be Red-Green Color Blindness (Deuteranopia as a sub-genre), instead of Haemophilia - especially interesting considering the allusions to 'opening the third eye' or being a 'GREENseer'. Just saying. Happens in around 1% of males. "1 in a 100".
kefkapalazzo1 even so, he would show trouble reading and slow reasoning skills from a younger age, which he doesn't. As puberty kicks in, he'd display a lack of romantic/sexual interest, but he seems pretty keen on Meera already. Physical traits would most likely be evidenced in puberty, yes.
It would be very interesting that red/green color blindness, however I think we've seen Bran looking at other houses' banners and I can't recall sometihng like that. And it is fiction, GRRM could've based the X ene theory/odds of Bran's case in Klinefelter Syndrome genetics while not adapting the other symptoms
Yeah Klinefelter causes extremely wide hips, early hair loss, and usually sterility. Granted bran is a young boy so this wouldn't be obvious but it seems like we would get a passing literary reference to at least one of these things.
Not to nitpick but I think it might be worth noting as someone with a degree in genetics and biotechnology, that penetrance; the extent that a gene or a group of genes are expressed. Can vary greatly and can be greatly affected by epigenetic mechanisms. Also although rare we have discovered some genes that are located on chromosomes that are not found on the X or Y sex chromosomes but have repeatedly proven to be directly under the control of the sex chromosomes, typically but not always the presence of the Y chromosome tends to be the chromosome that has the greater effect, although it should be noted we have discovered these mechanisms much more frequently in fruit flies (Drosophila Melansgaster) which should be noted use XY sex chromosomes like ourselves. However insects use a variety of different methods like Lepidoptera. I am only suggesting that we have to be careful how we discuss genetics as they have wide variation and adaptability. People often see genetics as a very strict dichotomy. Such as off or on, when the truth of the situation is rarely if ever so clear cut. The level or amount of gene expression operates frequently on a spectrum especially when dealing with rRNA that can act as a supressor or block expression completely or in very rare instances do the exact opposite and enhance expression. I just feel its something people should keep in mind. Also by the way the genes responsible for producing extra digits on hands and feet are infact a dominant gene. Despite it's very rare occurrence in the general population. Thank you.
I think Preston is operating under the assumption that George is not using advanced genetic theory. Just Mendel's Laws of Inheritance. After all, he is a layman. So it is a video about the genetics of Ice and Fire, not actual genetics, although they are similar in the basic concepts. Interesting point though.
This. We know there's environmental (or just plain mental) factors, but it's super likely there's multiple genes at play here too. Even Preston's example of eye color involves a handful of genes at least, and few known human traits involve only a single gene. What you said about expression operating on a spectrum is so important. Side note, the ways that life can turn spectra into discrete sections and discrete data into spectra impresses me so much. That's my favorite part of biochemistry, I think.
I thought Ned had woken his abilities when he was left in the dark on the black cell, would explain the dream about the bed soaked in blood of his sister.
Can I post spoilers of PJ's theory here? Too late; just read below. Ricardo Rodrigues has a point on greenseeing being a fictional form of what we know as Deuteranopia instead of XXY. Bran might not be a rumble-tumble-childhood kind of boy but many boys are such without being XXY. I also think it correlates symbolically a lot more; it is also ironic, as if normally everyone in westeros is colorblind except greeenseers. I am soooo looking forward to knowing more of House Whent. Why am saying this here? About this video and House Whent: I had a curious mental association just now as I was looking at the video's genetic possibilities maps and right after researched on house Whent (because of Catelyn's mother) and noticed their sigil. Nine bats on a golden field, and though displayed in a contradicting manner around the internet, some mention they must be in lines of four, three then two top-down-wise. It looked like a genetic possibilities chart. I got chills in my neck. It also looks like a family tree. And there has to be something to do with the way the Whents won position over the Lothstons (previous ruling house of harrenhal, sigil was just one bat on a field per bend silver and gold), and some Whents were magic practicioners in some level (rumours).
Tristan Bean ... Yup. Cognitive dissonance is very strong in the ASOIAF fandom. Some people just cant accept that this is not and has never been a conventional fantasy story.
Tristan Bean people, who say that his theories are crazy are mostly those who have only one theory cemented in their minds and who do not know the books, but claim so. Preston is possibly the person (and Order of the Green Hand) who knows the story better than Martin himself.
this must be so much work for just one video! i really wanna thank you for your amazing content. i follow you since season 3 and read the books because of this channel! keep it up preston!
I applaud the fact that you've really done your homework not just with A Song of Ice and Fire, and George R.R. Martin's other published works, but also in real life history and with genetics no less. Bravo.
Hmm...To me (BA in biology, but not a genetics expert by any means), the simplest explanation for why Bran is so special is that skinchanging/green-seeing is polygenic, with multiple genes contributing to it. So in theory, there could be an X-linked gene and an autosomal recessive gene that both contribute to it (or one gene's allele amplifies the effects of the other) & Bran happened to hit the jackpot. Disentangling that from the reader's side would be a nightmare obviously, but I think it would trackable on the author's end. (I'm doing something similar in the stories I'm writing, but, granted, I have waaaaay fewer families to keep track of than GRRM.) I agree that it makes sense to assume that the 13%-likely scenario is more likely what GRRM had in mind, but 3% odds aren't that obscure. You'd expect 3 out of 100 families to end up with that result, and there are a ton of families in the story. (Birthday-sharing probability paradox and all that: medium.com/i-math/the-birthday-problem-307f31a9ac6f ) So yeah, fascinating video & meticulous attention to detail as always...Bran having Klinefelter's is definitely an interesting option...I just think there are a few more possibilities potentially in play.
Would that also explain Bloodraven as well? He has a combination of Blackwood, Bracken and Targaryen genes. In fact it seems Aegon IV was deliberately trying to diversify and widen the genepool of his children by fathering bastards across the powerful noble houses. He was in love with his sister Shiera Seastar who also displayed a combination of traits different from the Targaryen genes. This was why Bittersteel and Bloodraven were fighting over her. What sort of genetic results could have resulted from the child of Bittersteeel (or Bloodraven) and Shiera Seastar?
Hard to say for sure, because if green-seeing is the product of multiple genes, it'd be extremely hard to figure out and track which bloodlines have the relevant genes. Hypothetical example: Let's say you need both a Warg-X gene and two autosomal recessive green genes (gg) to be a greenseer, but the gg genotype doesn't impart any special abilities by itself. The gg genes only have an effect if the person also has a warg-X gene to amplify. In that case, even people who were double autosomal recessive for the green/amplifier gene would seem normal--up until the point when they married into a family of wargs & accidentally birthed a greenseer. (ala Catelyn) But if the gg genes have no obvious effects without the warg-X gene, that would render those gg/green-seer/amplifier genes basically invisble on family trees. Even if some families (like the Targaryens) figured out how the X-linked part of the inheritance worked, they probably wouldn't know about the other genes. ...Which would probably produce a lot of confusion in terms of, "WHAT?! We've been making matches to preserve the X-linked inheritance! Why is this not working?!" So I think greenseeing/warging/dragon-riding being polygenic could explain why people have so much trouble reliably producing people with those abilities....It definitely seems like the Targaryens lost an important gene at some point and then tried to crossbreed themselves with other families in hopes of finding it again. The main reason I think that it greenseeing/warging/teke/dragon-riding being polygenic makes sense is that it's essentially a neurodevelopmental ability, and many neurodevelopmental traits are massively polygenic. It'd actually be kinda weird if teke wasn't polygenic, imho. (The other reason is that it's not uncommon for high school biology students to have to do punnet squares for 2-3 genes at the same time...There's a decent chance that layperson GRRM knows how to make a 16 or even 64 square punnet square. He could also know all about penetrance, gene regulation, influence due to microbiome, epigenetics, and all that jazz, but a 2-gene system is easy to track on the creator's side & hard to discern from the obsever's side.) As to the Shiera Seastar x Bittersteel cross, I have no idea...I don't think we have enough information to construct detailed genotype history from the reader perspective.
Yes from the moment he put his pen to paper writing the first page of A Game of Thrones he already had in mind the complex hereditary dynamics of Northern Westeros genetic pool.
I want to point out that there is another quite plausible reason for why the Night's King wasn't tolerated but Craster was: The Night's King was thousands of years ago and Craster is now. Why is that important? Well, because it's very clear that whatever happened with the Others thousands of years ago, including whatever peace treaty/deal may have been made, has largely been lost to legend and time. Only vague echoes of these things remain and the specifics have been completely forgotten. These things survive only in the form of traditions that nobody understands anymore. Several thousand years ago the people could've still remembered the deal they made and the importance of it and thus taken down the Night's King, whereas in the present (thousands of years later) that would've long been forgotten. Of course, that's assuming the Night's King was taken down for passing on skinchanging genes to the others and that this was against the rules. I actually tend to think that even after 100 years the people of Westeros had forgotten the specifics of the deal (or only the Lord Commanders ever knew of it in the first place) and that the Night's King was only upholding the humans' deal with the others as was expected of him. And the Starks and King Beyond the Wall rallying against him was because they had either forgotten or didn't know about this deal in the first place.
Blood Angel Damn, I had it right originally. No idea what Dragon Fox is going on about. Worried now that without the tone I imagined it might seem like I was agreeing with him/her.
If Littlefinger wanted Cat because of her double gene, it might be the reason why he's interested in Sansa too. He does refer to Cat as "impeccable bloodline" in season 1(when I assume they still tried to be accurate).
in LOVE with your channel, these theories are amazing! I know I should take them with a pinch of salt but they're all so compelling that I have to agree on some level with them all. can't wait for the next and final part!
Brilliant! thanks so much for this video. I really loved your genetics of dragons series, Preston, and good to see the same sort of analysis on the 'Ice' side
Bran The Builder planned it all !!! P.S. I think the whole idea of reverse expectations (female side being important instead of male) is really solid regarding GRRM writing style.
I'm very glad I waited until the end to comment. I was going to bring up Queen Vic's hemophilia and the disproportionate prevalence of it in European aristocracy.
You actually mentioned in an earlier vid how Ygritte, OSHA and the wildlings focus more on matrilineal is session (my mother, mother’s mother etc.) clever hint maybe? Wildlings know more than they let on...
Another point of evidence that the skinchanging gene is not Y-linked: if the Bael the Bard legend is to be believed, then the male line of the contemporary Starks (and probably the Karstarks too) is the line of Bael and not the male line of the first Starks of Winterfell, which is possibly extinct.
"There are ten hideously malformed jokers for every ace." Interesting line. One could argue Bran is the ace. So who are the jokers? Well we already have two candidates who seem to fit the bill. One is literally dressed like a joker. The other is hellbent on eldritch apocalypse. Euron has strongly hinted that he has skinchanger abilities and Patchface, liked Bran, survived something that unquestioningly should have killed him, and gained some sort of heightened awareness. If the Berick and Stoneheart rules apply, Jon is going to be a much darker character when he comes back, and his mind will have likely partially merged with Ghost's. And I've even seen some theories that Stoneheart wants to reanimate Robb, and to do that she would need Grey Wind's head, since Robb skinchanged Grey Wind when he died. The head was literally stitched onto the corpse so it's been heavily foreshadowed. Arya is another candidate with psychic abilities, and she's turning into a murderous psycho. Rickon is being raised among the Skagosi and will have been warging Shaggy Dog, the most wild and vicious of the dire wolves, with little to no knowledge of how this could affect his personality. Rickon may never even know what it means to be human given how he's been fully embracing his skinchanging abilities since he was a toddler, and given how fast wolves mature, Shaggy Dog is likely the more powerful personality. Rickon is going to become a rabid animal. Hell even Daenerys fits the bill. Her entire story seems to be revolving around her deciding to adopt an ends justify the means approach, culminating in her unleashing her dragons on King's Landing, which is still booby trapped with wildfire. Slaughtering half a million people she meant to save would definitely snap her sanity in half. And she has telepathic abilities to some degree through her bond with Drogon. If we want to step away from telepathy or supernatural senses for a moment we even have Tyrion. He's basically the Joker of Westeros. A man pushed so far beyond the brink due to the world rejecting him that he becomes vengeful and sadistic (GRRM says Tyrion is the villain), just wanting to watch the world burn. And Moqorro implied that despite lacking supernatural ability, Tyrion is as important as Euron or Daenerys. The small man who casts a large shadow. And thematically Tyrion is similar. He may not be supernatural but his intellect gives him a heightened awareness compared to the average person. And he has a similar thematic trade off in his hideous appearance (Bran lost his legs, Patchface and maybe Euron lost their sanity). Now I think King's Landing being destroyed will be an accident on Dany's part. But what if Tyrion learns about the wildfire from Jaime and deliberately keeps the information from Dany? Melisandre says there cannot be shadows without light. You're not going to find a brighter light. Including Berick and Stoneheart, I count ten hideously malformed jokers.
While I love most of your extended theories, especially putting in the science behind the story, this theory seems to have a few more errors than the dragon riding gene did... First and foremost being that it doesn't take much into consideration of the little genetics that GRRM does put into the first book. The Baratheon hair seems to suggest that the male line (and specifically male) will continue to pass on the same trait. I think that's enough said on the subject, as it applies to both the night king and craster. In addition to that, there is a fine line you tread between the traits presented, and the genes that influence them. The skinchanging and telepath genes could be separate, there could be multiple genes that come into play. If you were to have multiple genes affecting the trait, in addition to climatic elements, the fact that the stark clan has the trait makes more sense. If Catelyn carried one or more of the genes, then it would explain why Ned's children seem to present more than he did. This would also combine with the dragon riding gene, as Lyanna would have passed similar genes as Ned did, which when combined with the Targaryen blood would produce similar results. This also expands what you talked about in the video on the Night's King and Craster, where the Night King not only could have carried the stark genes more strongly than craster (where in a world where people may not understand the true genetics would be more impactful), but also Craster has a total of nineteen wives, which though is a lot by any definition, is nothing in comparison to a lord exercising first right. What could set apart Craster an the night king (besides the medeival understanding of genetics), is the number of children with the genes being sacrificed. The books, Gilly makes the claim that the white cold had come more often recently, meaning Craster likely hasn't been producing children as often as he may have in the past, again why he may be tolerated more. Finally, the others seem to all be male. This may not look like much, but in our world the Y chromosome is small to the extent that it passes on little genetic information. If the Y chromosome size is different in planetos, then the baratheon traits and the others make much more sense. Bran doesn't have to be Klinefelter to carry twice the gene if the gene could exist on the Y chromosome. It's indisputable that GRRM is smart enough to include the complicated nature of genetics in his writing, but that doesn't lead to the development of his characters. TLDR: GRRM probably had genetics in mind & at the same time, none of the characters in the world probably understand the genetics in the same way we do. This is probably why Craster is tolerated & the night king wasn't. In addition to two other factors, the 'not under my roof' mentality, and that a lord commander is a fully functioning lord, whom if practicing this incest sacrifice could produce many more from the 'comfort' of the wall than Craster ever could, especially if also practicing first night.
It would also quite nicely fit the genetics of dragonriding theory: single X: riding double X : hatching (telepathic control of phetuses within the egg)
What if in Targaryens there is some sort of virus/chance involved when trying to make dragon riders? This is why there's so many still births and dead lizard babies.
Great one!!! There had been an essay research on Jon Snows DNA once, him being the son of Lyanna and Rhaegar. And it proved that Jon would be NO DRAGON, only if his mother was "a DAYNE". Highly interesting. I personally keep saying that Dyanna Dayne is a DNA key. If you look at the Targaryen family tree and see events (Dunk and Egg) then you can come to the conclusion that the dragon gene is not the Targaryen gene, but a Dawn Age House gene, such as Hightower and Dayne. And Martin pointed to the importance of House Dayne for upcoming books. What made the others march South? Summerhall? The Dayne DNA, hedging dragons again? Bloodstone Emperor and Amethyst Empress genes? I am looking forward to the next part.
Wild Cards is a fantastic series, and importantly presents a superhero universe in which the "science" is completely logical and consistent. I think this aspect points very strongly to ASOIAF being sci-fi, rather than fantasy.
All 4 of my grandparents had brown eyes yet both of my parents, 2 of my uncles and both my aunts all have blue eyes. Only one uncle has brown eyes. Not sure how unlikely that is but I am pretty sure that Mendelian genetics is a massively simplified model.
Ahh, Preston Mendelssohn, father of modern game of thrones genetics. ..and sweet robin. Does littlefingers quest for harrenhall and to marry a Tully fit into this? Is he trying to find certain genes?
Love this video and the genetics of ice and fire series. Another possibility to consider is some characteristics are controlled by multiple genes, for example eye colour. Could be another interesting method to explore. Might explain the variation of ways telekinetic abilities manifest or how some greenseers are stronger than others?
This is amazing PJ!! I will be severely disappointed in ASOIAF if GRRM has not considered genetics this way, since it makes the story so much more interesting!
To be fair, we don't know if Ned or Cat had any special powers. Just because they are not addressed over the short time span we see them does not mean they didn't exist. Especially Ned. Who knows about Brandon or BenJen or Lyanna? Rickon dreamt the same dream at Bran when Ned died. But first. It may be that Rickon IS also talented, but through fate did not end up in Bran's situation. A bit like Neville Longbottom and Harry Pottee in that series.
+Alastair Bond Please leave people on the spectrum out of this. I am sure they want nothing to do with an alt-right incel wannabe tough guy obsessed with toxic masculinity who has nothing to do all day so he feels the need to answer every comment beneath a yt video with projections of somebody else's marital status.
Thanks Preston, as always ,,, I reckon the X chromosome similarity to haemophilia is the best explanation, as things don't always play out in terms of probability. Haempohilia can be caused by a random mutation which then is passed on as you explain. My grandmother had 7 sons, 6 were hamophiliacs. No prior history of the disease in the family. Odds go against those numbers
How are the Reeds explained if the skinchanging/greensheer gene is X-linked recessive? Their father Howland Reed had powers, so he would give his powerful x chromosome to Meera and not to Jojen. The only explanation I can think of is that their mother was a carrier and gave her powerful x chromosome to Jojen and her normal x chromosome to Meera, so Meera is also a carrier from her father.
I know this is off topic, but was thinking about how littlefinger ended in the show and wondered if you could do a video or a couple of videos about what they could have done instead? It would be cool to see what his alternative story line(s) would have played out with the characters currently left alive in the show. Not to mention how the trial should or would have played out! Please consider this, you're really good at GoT analysis.
Something that would be interesting to explore is the sheer pervasiveness of certain genetic traits among certain family lines and how they are explained by genetics. in particular the fact that the Lannisters have very pervasive blonde hair and green eyes across their current family tree and how this played off against the Baratheon genes (dark of hair). This was a major plot point in the first book as it was the darkness of hair that that was used as a conclusion that Cersei's children were not Robert's. It was more or less scientifically proven to be unlikely that they were his. With Robert, his children all look like him even though his has children with multiple random women. Why are his genes so strong? If it's a sci-fi story does Robert's DNA to some extent clone itself? Does that happen in other family lines? Is this due to ancient technology or centuries of local intermarriage?
What if it is not just genetics at play, like maybe skin changing genes are actually fairly common, but it requires those special environmental circumstances, perhaps something else in the world is happening which is "awakening" the abilities which is why Lyanna and Brandon and now all the stark children are experiencing the abilities
Problem is the genetics logic does not hold up past a high school level and I'm almost certain Preston knows that. IF 2 blue eyed people each had a parent with Brown yes and a parent with Blue eyes they would have a high chance of brown eyed children. As to Preston's later points about passing genes, it would make sense that Lords "Sell" their daughters to join houses, maybe they knew it was important at some point?
What do you think about Jon and the moments he share ghost senses and the times he Black out and go bserker is it unique to him like arya changes faces or bran abilities and I would like to know your thoughts is wargs could control dragons and they the reasons why the valryan freehold didn't invade the seven kingdoms
I have a question. isn't exactly related to the video, but involves ASOIAF. Preston wrote this in a reddit AMA three years ago: "I love Sweetrobin because he's real. He's actually a kid and not an adult in a child's body like Bran and Arya. I also feel sorry for him. He was dealt a bad hand and hope he makes it." I understand how Arya isn't exactly a kid anymore with all the people she's killed, but what I don't understand is how Preston considers Bran to be an adult in a child's body. He still seems like a child to me. Could someone explain this to me?
Very interesting theory and very well researched. Although I‘m having a hard time imagining GRRM having this all planned out. Sure he likes to write about genetics and seems to be familiar with the topic but would he really map out the genetic lineage of multiple generations of characters and calculate percentages and probabilities for the passing down of certain genes? Seems unlikely. Although I do wonder what is explanation for all Stark children being telepaths would be, if it‘s supposedly a 1 in 1000 chance (unless Bloodraven got something wrong).
He doesn't need to plan ahead the genetics if it is true. If GRRM had planned any of the genes, he can change the family lineage to whatever he wishes to fit it, before publication. He also hasn't given the entire lineages of the characters, just the patrilineal descent, which as Preston argues, leaves out a lot of the genetics.
It just seems to me like he decides who should be a skinchanger *first* an then maybe sort of tries to work it into the lineages. Like the Stark kids, they‘re pretty much the main characters so they‘re all skinchangers. Varamyr? He‘s just a one of villain, plus we don‘t want to many potential skinchangers north of the wall so all his kids are born without the gift. Maybe there is a bit more to it than that but I feel like Preston (as usual) is being a lot more in-depth than probably even GRRM himself.
This is the greatest channel to binge watch after re reading the entire series
the night is dark and full of "and this is a good place to stop" terrors :(
Dankest Memes 😂😂
The night is dark and full of turnips
@@standarddeviation7963 the turnip knight successor of the onion knight
When will Preston finish the book???
It has begun!!!!
He will be a worthy successor to grrm
Well well well
Sansa does not have a wolf anymore and that may explain her lack of skinchanging.
I would be a fool not to point out that Uncle Brandon and Lyanna spent a good deal of time riding horses and were called centaurs, suggesting they were linked to their horses. I can't say any animal Ned or Benjen spent time around in their childhood or adult life, but they may have had similar stories. Perhaps Ned didn't bond with any creature like his brother and sister, unless one of the oxen or ravens in the Eerie was special to him.
Maybe skinchanging is more than genetic, perhaps external factors are needed. You need the underlying genes there, yes, but something else should be there before they can unlock skinchanging. Such as low grade/rate radiation poisoning acting on the gene, then trauma to unlock it properly.
Well starting my Ned/Oxen crackship now. Thank you
If Cat is single X my bet is house Tully NOT being carriers of Skinchanging and Greenseeing.
House Whent is heavily implied to be connected to Lothston which are more likely to be Skinchangers.
Don't worry Preston, as long as we get the High Septon he can annul all of these genes!
😂
Klinefelter Syndrome has other phenotypical and mental markers which Bran doesn't exhibit.
Also, a more typical example of a X Recessive Trait to explain that type of genetic heritage would be Red-Green Color Blindness (Deuteranopia as a sub-genre), instead of Haemophilia - especially interesting considering the allusions to 'opening the third eye' or being a 'GREENseer'. Just saying. Happens in around 1% of males. "1 in a 100".
Ricardo Rodrigues well to be fair bran is prepubescent so maybe the physical aspect isn’t that apparent. Nothing else for your other points though lol
kefkapalazzo1 even so, he would show trouble reading and slow reasoning skills from a younger age, which he doesn't. As puberty kicks in, he'd display a lack of romantic/sexual interest, but he seems pretty keen on Meera already. Physical traits would most likely be evidenced in puberty, yes.
Liking for the pun lol
It would be very interesting that red/green color blindness, however I think we've seen Bran looking at other houses' banners and I can't recall sometihng like that.
And it is fiction, GRRM could've based the X ene theory/odds of Bran's case in Klinefelter Syndrome genetics while not adapting the other symptoms
Yeah Klinefelter causes extremely wide hips, early hair loss, and usually sterility. Granted bran is a young boy so this wouldn't be obvious but it seems like we would get a passing literary reference to at least one of these things.
Not to nitpick but I think it might be worth noting as someone with a degree in genetics and biotechnology, that penetrance; the extent that a gene or a group of genes are expressed. Can vary greatly and can be greatly affected by epigenetic mechanisms.
Also although rare we have discovered some genes that are located on chromosomes that are not found on the X or Y sex chromosomes but have repeatedly proven to be directly under the control of the sex chromosomes, typically but not always the presence of the Y chromosome tends to be the chromosome that has the greater effect, although it should be noted we have discovered these mechanisms much more frequently in fruit flies (Drosophila Melansgaster) which should be noted use XY sex chromosomes like ourselves. However insects use a variety of different methods like Lepidoptera.
I am only suggesting that we have to be careful how we discuss genetics as they have wide variation and adaptability. People often see genetics as a very strict dichotomy. Such as off or on, when the truth of the situation is rarely if ever so clear cut. The level or amount of gene expression operates frequently on a spectrum especially when dealing with rRNA that can act as a supressor or block expression completely or in very rare instances do the exact opposite and enhance expression.
I just feel its something people should keep in mind.
Also by the way the genes responsible for producing extra digits on hands and feet are infact a dominant gene. Despite it's very rare occurrence in the general population.
Thank you.
Excellent discussion!! I was going to comment about penetrance but you gave a phenomenal discussion!!
I think Preston is operating under the assumption that George is not using advanced genetic theory. Just Mendel's Laws of Inheritance. After all, he is a layman.
So it is a video about the genetics of Ice and Fire, not actual genetics, although they are similar in the basic concepts.
Interesting point though.
This. We know there's environmental (or just plain mental) factors, but it's super likely there's multiple genes at play here too. Even Preston's example of eye color involves a handful of genes at least, and few known human traits involve only a single gene. What you said about expression operating on a spectrum is so important. Side note, the ways that life can turn spectra into discrete sections and discrete data into spectra impresses me so much. That's my favorite part of biochemistry, I think.
Jooooger agreed.
its*
18:13 That Lannister art is impressive
None So Awesome, Bro
Queen in the North.
Chad Summerchild
LBL is SOOO awesome BRO
Chad Summerchild Queen in the North!
Craster has a daughter??? I didn't know that!
willy Wowzers I should apologize.
I thought Ned had woken his abilities when he was left in the dark on the black cell, would explain the dream about the bed soaked in blood of his sister.
Can I post spoilers of PJ's theory here?
Too late; just read below.
Ricardo Rodrigues has a point on greenseeing being a fictional form of what we know as Deuteranopia instead of XXY.
Bran might not be a rumble-tumble-childhood kind of boy but many boys are such without being XXY.
I also think it correlates symbolically a lot more; it is also ironic, as if normally everyone in westeros is colorblind except greeenseers.
I am soooo looking forward to knowing more of House Whent.
Why am saying this here? About this video and House Whent: I had a curious mental association just now as I was looking at the video's genetic possibilities maps and right after researched on house Whent (because of Catelyn's mother) and noticed their sigil. Nine bats on a golden field, and though displayed in a contradicting manner around the internet, some mention they must be in lines of four, three then two top-down-wise. It looked like a genetic possibilities chart. I got chills in my neck. It also looks like a family tree. And there has to be something to do with the way the Whents won position over the Lothstons (previous ruling house of harrenhal, sigil was just one bat on a field per bend silver and gold), and some Whents were magic practicioners in some level (rumours).
People say your theories are crazy but really all you do is just collect evidence and come to completely reasonable conclusions.
Tristan Bean ... Yup. Cognitive dissonance is very strong in the ASOIAF fandom. Some people just cant accept that this is not and has never been a conventional fantasy story.
Tristan Bean people, who say that his theories are crazy are mostly those who have only one theory cemented in their minds and who do not know the books, but claim so. Preston is possibly the person (and Order of the Green Hand) who knows the story better than Martin himself.
Some of his theories are pretty out-there, others are quite plausible. It doesn't have to be one or the other.
While I think he's very good at theorizing he does take literary coincidences as evidence too much id say
Lol the same can be said for a lot of conspiracy theories
this must be so much work for just one video! i really wanna thank you for your amazing content. i follow you since season 3 and read the books because of this channel! keep it up preston!
I don't question Martin's understanding of genetics, but rather if characters are motivated by an awareness of genetics within the story.
Good god we need that book to come out soon
You think way too much into this stuff but that's why I love you
Jew jew! Y ddraig goch!
I will obviously have to watch the other parts before I continue with this one to be perfectly prepared! Thanks for your crazy good analysis
Preston and Order of the Green Hand vids in one day? Me gusta
I applaud the fact that you've really done your homework not just with A Song of Ice and Fire, and George R.R. Martin's other published works, but also in real life history and with genetics no less. Bravo.
Hmm...To me (BA in biology, but not a genetics expert by any means), the simplest explanation for why Bran is so special is that skinchanging/green-seeing is polygenic, with multiple genes contributing to it. So in theory, there could be an X-linked gene and an autosomal recessive gene that both contribute to it (or one gene's allele amplifies the effects of the other) & Bran happened to hit the jackpot.
Disentangling that from the reader's side would be a nightmare obviously, but I think it would trackable on the author's end. (I'm doing something similar in the stories I'm writing, but, granted, I have waaaaay fewer families to keep track of than GRRM.)
I agree that it makes sense to assume that the 13%-likely scenario is more likely what GRRM had in mind, but 3% odds aren't that obscure. You'd expect 3 out of 100 families to end up with that result, and there are a ton of families in the story. (Birthday-sharing probability paradox and all that: medium.com/i-math/the-birthday-problem-307f31a9ac6f )
So yeah, fascinating video & meticulous attention to detail as always...Bran having Klinefelter's is definitely an interesting option...I just think there are a few more possibilities potentially in play.
Diana Crow
That sounds very plausible. I don't think it's pure X chromosome inheritance
Diana Crow
I think you may have provided the best explanation. Don't buy the xxy theory at all.
Would that also explain Bloodraven as well? He has a combination of Blackwood, Bracken and Targaryen genes. In fact it seems Aegon IV was deliberately trying to diversify and widen the genepool of his children by fathering bastards across the powerful noble houses. He was in love with his sister Shiera Seastar who also displayed a combination of traits different from the Targaryen genes. This was why Bittersteel and Bloodraven were fighting over her. What sort of genetic results could have resulted from the child of Bittersteeel (or Bloodraven) and Shiera Seastar?
Hard to say for sure, because if green-seeing is the product of multiple genes, it'd be extremely hard to figure out and track which bloodlines have the relevant genes.
Hypothetical example: Let's say you need both a Warg-X gene and two autosomal recessive green genes (gg) to be a greenseer, but the gg genotype doesn't impart any special abilities by itself. The gg genes only have an effect if the person also has a warg-X gene to amplify. In that case, even people who were double autosomal recessive for the green/amplifier gene would seem normal--up until the point when they married into a family of wargs & accidentally birthed a greenseer. (ala Catelyn)
But if the gg genes have no obvious effects without the warg-X gene, that would render those gg/green-seer/amplifier genes basically invisble on family trees. Even if some families (like the Targaryens) figured out how the X-linked part of the inheritance worked, they probably wouldn't know about the other genes.
...Which would probably produce a lot of confusion in terms of, "WHAT?! We've been making matches to preserve the X-linked inheritance! Why is this not working?!"
So I think greenseeing/warging/dragon-riding being polygenic could explain why people have so much trouble reliably producing people with those abilities....It definitely seems like the Targaryens lost an important gene at some point and then tried to crossbreed themselves with other families in hopes of finding it again.
The main reason I think that it greenseeing/warging/teke/dragon-riding being polygenic makes sense is that it's essentially a neurodevelopmental ability, and many neurodevelopmental traits are massively polygenic. It'd actually be kinda weird if teke wasn't polygenic, imho.
(The other reason is that it's not uncommon for high school biology students to have to do punnet squares for 2-3 genes at the same time...There's a decent chance that layperson GRRM knows how to make a 16 or even 64 square punnet square. He could also know all about penetrance, gene regulation, influence due to microbiome, epigenetics, and all that jazz, but a 2-gene system is easy to track on the creator's side & hard to discern from the obsever's side.)
As to the Shiera Seastar x Bittersteel cross, I have no idea...I don't think we have enough information to construct detailed genotype history from the reader perspective.
Your explanation certainly makes more sense and feels more likely than Bran having a genetic birth defect.
Just when I thought I wasn't getting a Preston jacobs video this week......BAM*
I love your hypothetical genetics videos, Preston; they're my absolute favorites!
GRRM planned it all !!!
Connor Glass
He played us like a damn fiddle!!
Dragon Fox how do you know this??
Dragon Fox Ughhhhhhh Get a grip
Yes from the moment he put his pen to paper writing the first page of A Game of Thrones he already had in mind the complex hereditary dynamics of Northern Westeros genetic pool.
@Dragon Fox Stop being an asshole. Preston has some great theories, and I don't agree with all of them, but it's no reason to insult him.
The Queen Victoria Xplanation blew my mind !
You’re just amazing 🥺
I feel like I learn way more about genetics here than I did in my one year of bio way back in high school
WHAT?! Is it my birthday??? I'm so freakin excited for this expect a binge watch to follow..you know what time it is😎
Man..i just discovered your season x watch series.I have no idea why i didnt saw them before but they are amazing. Gilber for High king
I want to point out that there is another quite plausible reason for why the Night's King wasn't tolerated but Craster was: The Night's King was thousands of years ago and Craster is now. Why is that important? Well, because it's very clear that whatever happened with the Others thousands of years ago, including whatever peace treaty/deal may have been made, has largely been lost to legend and time. Only vague echoes of these things remain and the specifics have been completely forgotten. These things survive only in the form of traditions that nobody understands anymore. Several thousand years ago the people could've still remembered the deal they made and the importance of it and thus taken down the Night's King, whereas in the present (thousands of years later) that would've long been forgotten.
Of course, that's assuming the Night's King was taken down for passing on skinchanging genes to the others and that this was against the rules. I actually tend to think that even after 100 years the people of Westeros had forgotten the specifics of the deal (or only the Lord Commanders ever knew of it in the first place) and that the Night's King was only upholding the humans' deal with the others as was expected of him. And the Starks and King Beyond the Wall rallying against him was because they had either forgotten or didn't know about this deal in the first place.
where are the chad summerchild shirts
HKSATWOC DUH Finally, someone unafraid to ask the real questions. I see you too are a man of taste.
Dude wtf
Dragon Fox That is certainly a... interpretation. Edit: Grammar, hopefully corrected.
Blood Angel Damn, I had it right originally. No idea what Dragon Fox is going on about. Worried now that without the tone I imagined it might seem like I was agreeing with him/her.
Thanks, Preston. I really enjoy your videos.
The one dislike should be sacrificed to the Others
He's married? To a strong feminist I'm sure.
Their family tree needs to be thouroghly checked first, though, to make sure we're not giving the Others any important genes.
Kind of suspicious that Preston knows this much about genes and splicing etc, but cant seem to be able to fix Carmine.
Gekokujo76 ?
All the best mad scientists keep their early, flawed creations around to remind themselves not to become too satisfied with their own genius.
If Littlefinger wanted Cat because of her double gene, it might be the reason why he's interested in Sansa too. He does refer to Cat as "impeccable bloodline" in season 1(when I assume they still tried to be accurate).
in LOVE with your channel, these theories are amazing! I know I should take them with a pinch of salt but they're all so compelling that I have to agree on some level with them all. can't wait for the next and final part!
Brilliant! thanks so much for this video. I really loved your genetics of dragons series, Preston, and good to see the same sort of analysis on the 'Ice' side
Yes! a new video, just what i need when getting home from work
Bran The Builder planned it all !!!
P.S. I think the whole idea of reverse expectations (female side being important instead of male) is really solid regarding GRRM writing style.
I'm very glad I waited until the end to comment. I was going to bring up Queen Vic's hemophilia and the disproportionate prevalence of it in European aristocracy.
It's after midnight in my country. the exam is at nine tomorrow
You actually mentioned in an earlier vid how Ygritte, OSHA and the wildlings focus more on matrilineal is session (my mother, mother’s mother etc.) clever hint maybe? Wildlings know more than they let on...
Another point of evidence that the skinchanging gene is not Y-linked: if the Bael the Bard legend is to be believed, then the male line of the contemporary Starks (and probably the Karstarks too) is the line of Bael and not the male line of the first Starks of Winterfell, which is possibly extinct.
I’m so glad you brought up Kleinsfelters syndrome because I’ve always wondered if that could play into confusing genetic anomalies in asoiaf.
Thanks Preston. You just made my Sunday.
love this series and how far you are going here. Thanks !!
"There are ten hideously malformed jokers for every ace." Interesting line. One could argue Bran is the ace. So who are the jokers?
Well we already have two candidates who seem to fit the bill. One is literally dressed like a joker. The other is hellbent on eldritch apocalypse. Euron has strongly hinted that he has skinchanger abilities and Patchface, liked Bran, survived something that unquestioningly should have killed him, and gained some sort of heightened awareness. If the Berick and Stoneheart rules apply, Jon is going to be a much darker character when he comes back, and his mind will have likely partially merged with Ghost's. And I've even seen some theories that Stoneheart wants to reanimate Robb, and to do that she would need Grey Wind's head, since Robb skinchanged Grey Wind when he died. The head was literally stitched onto the corpse so it's been heavily foreshadowed. Arya is another candidate with psychic abilities, and she's turning into a murderous psycho. Rickon is being raised among the Skagosi and will have been warging Shaggy Dog, the most wild and vicious of the dire wolves, with little to no knowledge of how this could affect his personality. Rickon may never even know what it means to be human given how he's been fully embracing his skinchanging abilities since he was a toddler, and given how fast wolves mature, Shaggy Dog is likely the more powerful personality. Rickon is going to become a rabid animal.
Hell even Daenerys fits the bill. Her entire story seems to be revolving around her deciding to adopt an ends justify the means approach, culminating in her unleashing her dragons on King's Landing, which is still booby trapped with wildfire. Slaughtering half a million people she meant to save would definitely snap her sanity in half. And she has telepathic abilities to some degree through her bond with Drogon.
If we want to step away from telepathy or supernatural senses for a moment we even have Tyrion. He's basically the Joker of Westeros. A man pushed so far beyond the brink due to the world rejecting him that he becomes vengeful and sadistic (GRRM says Tyrion is the villain), just wanting to watch the world burn. And Moqorro implied that despite lacking supernatural ability, Tyrion is as important as Euron or Daenerys. The small man who casts a large shadow. And thematically Tyrion is similar. He may not be supernatural but his intellect gives him a heightened awareness compared to the average person. And he has a similar thematic trade off in his hideous appearance (Bran lost his legs, Patchface and maybe Euron lost their sanity). Now I think King's Landing being destroyed will be an accident on Dany's part. But what if Tyrion learns about the wildfire from Jaime and deliberately keeps the information from Dany? Melisandre says there cannot be shadows without light. You're not going to find a brighter light.
Including Berick and Stoneheart, I count ten hideously malformed jokers.
I have willingly learned more about geneology from Preston than I ever did in school.
Preston you're spending more time on this book than George R R Martin.😅
I came for Secrets of Craster's Keep, I stayed for Genetics of Dragons and War
Love the t-shirt, btw
This is a great work, congrats, you blew my mind !
This was so great and timely. Really reignited my asoiaf love which was beginning to wane
AND WE'RE BACKKKKKKKK
While I love most of your extended theories, especially putting in the science behind the story, this theory seems to have a few more errors than the dragon riding gene did... First and foremost being that it doesn't take much into consideration of the little genetics that GRRM does put into the first book. The Baratheon hair seems to suggest that the male line (and specifically male) will continue to pass on the same trait. I think that's enough said on the subject, as it applies to both the night king and craster. In addition to that, there is a fine line you tread between the traits presented, and the genes that influence them. The skinchanging and telepath genes could be separate, there could be multiple genes that come into play. If you were to have multiple genes affecting the trait, in addition to climatic elements, the fact that the stark clan has the trait makes more sense. If Catelyn carried one or more of the genes, then it would explain why Ned's children seem to present more than he did. This would also combine with the dragon riding gene, as Lyanna would have passed similar genes as Ned did, which when combined with the Targaryen blood would produce similar results. This also expands what you talked about in the video on the Night's King and Craster, where the Night King not only could have carried the stark genes more strongly than craster (where in a world where people may not understand the true genetics would be more impactful), but also Craster has a total of nineteen wives, which though is a lot by any definition, is nothing in comparison to a lord exercising first right. What could set apart Craster an the night king (besides the medeival understanding of genetics), is the number of children with the genes being sacrificed. The books, Gilly makes the claim that the white cold had come more often recently, meaning Craster likely hasn't been producing children as often as he may have in the past, again why he may be tolerated more. Finally, the others seem to all be male. This may not look like much, but in our world the Y chromosome is small to the extent that it passes on little genetic information. If the Y chromosome size is different in planetos, then the baratheon traits and the others make much more sense. Bran doesn't have to be Klinefelter to carry twice the gene if the gene could exist on the Y chromosome. It's indisputable that GRRM is smart enough to include the complicated nature of genetics in his writing, but that doesn't lead to the development of his characters.
TLDR: GRRM probably had genetics in mind & at the same time, none of the characters in the world probably understand the genetics in the same way we do. This is probably why Craster is tolerated & the night king wasn't. In addition to two other factors, the 'not under my roof' mentality, and that a lord commander is a fully functioning lord, whom if practicing this incest sacrifice could produce many more from the 'comfort' of the wall than Craster ever could, especially if also practicing first night.
You could write a thesis on this, amazing.
Thank you for your time and efforts, Preston. You fucking legend
It would also quite nicely fit the genetics of dragonriding theory:
single X: riding
double X : hatching (telepathic control of phetuses within the egg)
What if in Targaryens there is some sort of virus/chance involved when trying to make dragon riders? This is why there's so many still births and dead lizard babies.
Great one!!! There had been an essay research on Jon Snows DNA once, him being the son of Lyanna and Rhaegar. And it proved that Jon would be NO DRAGON, only if his mother was "a DAYNE". Highly interesting. I personally keep saying that Dyanna Dayne is a DNA key. If you look at the Targaryen family tree and see events (Dunk and Egg) then you can come to the conclusion that the dragon gene is not the Targaryen gene, but a Dawn Age House gene, such as Hightower and Dayne. And Martin pointed to the importance of House Dayne for upcoming books. What made the others march South? Summerhall? The Dayne DNA, hedging dragons again? Bloodstone Emperor and Amethyst Empress genes? I am looking forward to the next part.
I love your genetics videos. Can’t wait for part 5!
Another great video, Ser Preston Boris Jacobs (I haven't even watched it yet, but I know it'll be excellent)
Wild Cards is a fantastic series, and importantly presents a superhero universe in which the "science" is completely logical and consistent. I think this aspect points very strongly to ASOIAF being sci-fi, rather than fantasy.
All 4 of my grandparents had brown eyes yet both of my parents, 2 of my uncles and both my aunts all have blue eyes. Only one uncle has brown eyes. Not sure how unlikely that is but I am pretty sure that Mendelian genetics is a massively simplified model.
I've been waiting for this! Can't wait for Part 5 :)
As usual, it's an amazing job! Thank you!
Ahh, Preston Mendelssohn, father of modern game of thrones genetics. ..and sweet robin. Does littlefingers quest for harrenhall and to marry a Tully fit into this? Is he trying to find certain genes?
The Lady Olenna Tyrell
Who knows what game Littlefinger is playing?
Love this video and the genetics of ice and fire series. Another possibility to consider is some characteristics are controlled by multiple genes, for example eye colour. Could be another interesting method to explore. Might explain the variation of ways telekinetic abilities manifest or how some greenseers are stronger than others?
This is amazing PJ!! I will be severely disappointed in ASOIAF if GRRM has not considered genetics this way, since it makes the story so much more interesting!
awesome series, you are doing a great job!
To be fair, we don't know if Ned or Cat had any special powers. Just because they are not addressed over the short time span we see them does not mean they didn't exist. Especially Ned. Who knows about Brandon or BenJen or Lyanna?
Rickon dreamt the same dream at Bran when Ned died. But first. It may be that Rickon IS also talented, but through fate did not end up in Bran's situation. A bit like Neville Longbottom and Harry Pottee in that series.
All hail Preston!
+Alastair Bond
Please leave people on the spectrum out of this. I am sure they want nothing to do with an alt-right incel wannabe tough guy obsessed with toxic masculinity who has nothing to do all day so he feels the need to answer every comment beneath a yt video with projections of somebody else's marital status.
Are the men of the sisters sacrificing dwarfs to the sea the same thing as the Other sacrifice but to the Squishers?
My favorite one! Thank you!
Thanks Preston, as always ,,, I reckon the X chromosome similarity to haemophilia is the best explanation, as things don't always play out in terms of probability. Haempohilia can be caused by a random mutation which then is passed on as you explain. My grandmother had 7 sons, 6 were hamophiliacs. No prior history of the disease in the family. Odds go against those numbers
Preston! I have shit to do! I literally stop life to watch your videos :)
PRESTOOOOON!
It's 2 AM and I was literally moving my cursor to top right edge to close browser when I got the notification...
*sigh*
Accept your fate and Do Eeeeetttt
Love your videos. Love your accents even more! Lol.
I would say Dany’s power was being fireproof. No?
How are the Reeds explained if the skinchanging/greensheer gene is X-linked recessive? Their father Howland Reed had powers, so he would give his powerful x chromosome to Meera and not to Jojen. The only explanation I can think of is that their mother was a carrier and gave her powerful x chromosome to Jojen and her normal x chromosome to Meera, so Meera is also a carrier from her father.
Mind-blown = well done PJ
i have no idea what the video was about. but i loved it
I’ve been waiting for this 🍿
GRRM's entire thing is "Do some trippy ass DMT laden drugs and get super powers."
I know this is off topic, but was thinking about how littlefinger ended in the show and wondered if you could do a video or a couple of videos about what they could have done instead? It would be cool to see what his alternative story line(s) would have played out with the characters currently left alive in the show. Not to mention how the trial should or would have played out! Please consider this, you're really good at GoT analysis.
how did i know from the earliest mention of sex linked genes in this video that you would use Kleinfelter to explain Bran, good job Preston
that subconscious womb telekinesis gets me everytime :D
It's nuts right
Doctor Tachyon is such a chill fun dude.
Something that would be interesting to explore is the sheer pervasiveness of certain genetic traits among certain family lines and how they are explained by genetics. in particular the fact that the Lannisters have very pervasive blonde hair and green eyes across their current family tree and how this played off against the Baratheon genes (dark of hair). This was a major plot point in the first book as it was the darkness of hair that that was used as a conclusion that Cersei's children were not Robert's. It was more or less scientifically proven to be unlikely that they were his. With Robert, his children all look like him even though his has children with multiple random women. Why are his genes so strong? If it's a sci-fi story does Robert's DNA to some extent clone itself? Does that happen in other family lines? Is this due to ancient technology or centuries of local intermarriage?
I'm a simple man. I see a Preston video, I click, I like.
Strange how the ww return when the starks marry andal blood..and have a load of wargs
tomorow I have physicochemistry exam. Hope this video helps!
What if it is not just genetics at play, like maybe skin changing genes are actually fairly common, but it requires those special environmental circumstances, perhaps something else in the world is happening which is "awakening" the abilities which is why Lyanna and Brandon and now all the stark children are experiencing the abilities
this video is excelent for a nice afternoon sleep...
Problem is the genetics logic does not hold up past a high school level and I'm almost certain Preston knows that. IF 2 blue eyed people each had a parent with Brown yes and a parent with Blue eyes they would have a high chance of brown eyed children. As to Preston's later points about passing genes, it would make sense that Lords "Sell" their daughters to join houses, maybe they knew it was important at some point?
The difference between the Night's King and Craster is that Craster isn't a Stark, isn't producing warg children - or am I missing something?
What do you think about Jon and the moments he share ghost senses and the times he Black out and go bserker is it unique to him like arya changes faces or bran abilities and I would like to know your thoughts is wargs could control dragons and they the reasons why the valryan freehold didn't invade the seven kingdoms
Everything was awesome!
I have a question. isn't exactly related to the video, but involves ASOIAF. Preston wrote this in a reddit AMA three years ago: "I love Sweetrobin because he's real. He's actually a kid and not an adult in a child's body like Bran and Arya. I also feel sorry for him. He was dealt a bad hand and hope he makes it." I understand how Arya isn't exactly a kid anymore with all the people she's killed, but what I don't understand is how Preston considers Bran to be an adult in a child's body. He still seems like a child to me. Could someone explain this to me?
Just what I hoped for 👌
and analysis becomes even more complex when considering a trait that is governed by multiple genes
i love the thematic irony of characters and readers obsessing over patrilineal inheritence when it was the matrilineal side all along
Yay! New Preston video.
Very interesting theory and very well researched. Although I‘m having a hard time imagining GRRM having this all planned out. Sure he likes to write about genetics and seems to be familiar with the topic but would he really map out the genetic lineage of multiple generations of characters and calculate percentages and probabilities for the passing down of certain genes? Seems unlikely. Although I do wonder what is explanation for all Stark children being telepaths would be, if it‘s supposedly a 1 in 1000 chance (unless Bloodraven got something wrong).
TheLetterM I am sure he only needed only 2 or 3 generations in the beginning. As he writes more, he makes up more.
He doesn't need to plan ahead the genetics if it is true. If GRRM had planned any of the genes, he can change the family lineage to whatever he wishes to fit it, before publication. He also hasn't given the entire lineages of the characters, just the patrilineal descent, which as Preston argues, leaves out a lot of the genetics.
It just seems to me like he decides who should be a skinchanger *first* an then maybe sort of tries to work it into the lineages. Like the Stark kids, they‘re pretty much the main characters so they‘re all skinchangers. Varamyr? He‘s just a one of villain, plus we don‘t want to many potential skinchangers north of the wall so all his kids are born without the gift. Maybe there is a bit more to it than that but I feel like Preston (as usual) is being a lot more in-depth than probably even GRRM himself.
If he planned whole histories and family tree-lines and mapped continents, most likely he planned this aswell!