I want a modal baby.
How close are we to this tech?
I think people could probably calculate the modal genotype now, although I don't think anyone's ever tried it and maybe it would take a few years.
I imagine the process would be something like someone reading a random egg cell from you and a random sperm cell from your husband, putting it in a computer, spell-checking it, then printing out the genotype for the baby which gets inserted back in the egg. Even the back-in-the-egg insertion part would require something like cloning, which we can't do for humans yet, but the real trouble would be printing out DNA. This is way beyond what we can do now, but genetics seems kind of Moore's Law-y and I could imagine genetic printing only taking a couple of PCR-level insights.
I predict we will get better at this very quickly, but I'm not even a knowledgeable amateur in any of the appropriate fields. I would say (wild guess) 33% chance it happens in your reproductive lifetime, 66% that it happens in your actual lifetime.
One problem immediately comes to mind: if universally implemented, natural evolution would stop. If you're counting on engineered evolution, this may not be an issue.
Edited at 2012-12-09 05:28 am (UTC)
I don't think evolution is going to do much in the couple of centuries max we have before singularity anyway.
So, are you planning out the "story arcs" of your various blog posts, or are you just that clever with the backreferences?
I'm not sure if I should shiver or applaud.
So I'll just say, thank you for all the time you put into writing and sharing and engaging with ideas.
No, I just tend to think about the same things all the time :)
Thanks for the nice words.
Most highly-heritable traits are bell-curve distributed. Is this consistant with what we'd expect to see if the "modal human" school of thought were largely correct? The name suggests that it may not be: the mode of a bell curve is at the center, which often isn't what we'd expect to be the optimal value (the center of the height distribution is arguably near-optimal, but not so much for intelligence).
It is consistent, because we would expect the number of mutations to be bell-curve distributed.
Let my try again now that my brain has woken up.
The "modal human" is not one who's traits are modal, but one who's genes all have the variant that the most humans have (the genes are modal). The hypothesis of the "modal human" school of thought is roughly "IQ of a person = IQ of modal human - number of mutations of the person". Since we expect the number of mutations to be bell-curve distributed we also expect the IQ to be bell-curve distributed.
Edited at 2012-12-09 10:54 am (UTC)
"I can not tell you how much money I would pay to watch a full-on fight between the social justice people and the bioethicists."
Can we harness viewers like you as a funding source to develop this technology? =P
"People with more load than average are allowed to bring their load down to average, but no one can go any further than that."
This suggests a science-fictional world: Suppose by some quirk of legislation this did become the law. But suppose the technology develops to let you choose which mutations to reverse, so long as you don't bring the total number below the census average.
Then in order to optimize your baby for some particular criterion such as height, it is an advantage to start with a higher mutational load, so that you can reverse lots of height-affecting mutations.
We might then expect the population to split off in a few different directions – these people value height, those IQ – and for these groups to be genetically distinguishable within a very few generations.
Kind of reminds me of choosing character traits in a game like, say, Sims 2. You were only given half the number of points needed to make the perfect Sim, hence you could make them an average person all around or focus on a few things like making the Sim outgoing or tidy.
What I always ended up with were people with maximized one or two traits who were entirely different from one another. It's too bad that didn't show in their appearance. At best I only saw the contrast in their behavior, and even then only in their spontaneous behavior (and I tended to micromanage).
So the "quirk of legislation" already exists as a game mechanic, it's just probably not as executed as well as it could have been.
One potential problem in this onrushing future of modal babies: We might lose from human diversity any significant phenotypes that correlate with higher mutational load. For example, some apparently serious people believe that autism is driven by high mutational load. If it is, then a future with very little mutational load could be a future with very few autistic people. I think that that would be contrary to the preferences of a bunch of autistic people alive today.
> I think that that would be contrary to the preferences of a bunch of autistic people alive today.
I just want to recommend some marginally related stuff you would enjoy reading. This time it isn't Catholic propaganda but anti-IQ-propaganda of the convincing kind. Four blog posts by statistician Cosma Shalizi there
, and there
An obvious objection to the first post is that accent will perfectly follow the parents one was raised with: adoptees will have the accent of their adoptive parents and siblings. Is the same true of IQ?
The genetically modal human would lack lactose tolerance, European HIV resistance, and putative Ashkenazi genes for high intelligence. I know, you say just eliminate the bad mutations, not good polymorphisms, but we don't know which are which, except for the really bad mutations.
"Objective" health and attractiveness: I've read the immune system has two big components, aimed at parasites or germs, and Native Americans are skewed toward parasites. This isn't objectively bad; it made sense in their environment. As for attractiveness, umm. People may generally like symmetry and signs of youth, but otherwise there's a lot of cultural or individual variation.
And in general, the ideal immune system genes are highly non-modal ones, so you can survive what's killing everyone else.
Basic idea reminds me of the Children of the Lens.
As for basic technique, there's the Gattaca approach of screening embryos. Aka preimplantation genetic diagnosis. Won't get you perfection but might let you sample from the nice tail of the bell curve.
Edited at 2012-12-09 11:38 am (UTC)
2012-12-09 07:15 pm (UTC)
> The genetically modal human would lack lactose tolerance
This is the opposite of what Scott said. ("The genetically modal human would have lactose tolerance" is *also* the opposite of what Scott said.) Read his post again, or read the Wikipedia articles on polymorphism and mutation.
I don't think I like the distinction between polymorphism and mutation (speaking as a geneticist, I use the terms mostly interchangeably - this is possibly wrong but I've never noticed anyone picking me up on it). A polymorphism, to my understanding, is just a mutation which is observed in a lot of people, a mutation that spread and got fixed.
Firstly, going with your definitions for now, the idea that polymorphisms are common and don't cause disease but mutations are rare and do is incorrect. dbSNP, the database of Single Nucleotide Polymorphisms, carries many variants which are disease causing, some of which are pretty common. My own field, which is the genetics of deafness and progressive hearing loss, is a perfect example; more than half the population over 70 have a hearing loss of 25dB or more which would benefit from a hearing aid. Age-related hearing loss has a genetic component (about 50%) - the small mutations causing some (most) people to lose their hearing as they get older are most definitely present in a huge proportion of the population. So when you discuss the millions of small changes which lead to differences in characteristics such as intelligence, and you say "Enter mutational load, the idea that everyone has a different set of harmful mutations and different people may have different numbers" - those harmful mutations you're talking about are mostly going to be the polymorphisms that are common in the population.
Secondly, I don't think it's as easy as correcting the harmful polymorphisms/mutations. Gene and polymorphism effects are not independent. A polymorphism may exist that confers, say, exceptional strength upon an individual but does so at the cost of later muscle wastage. Or one may exist that contributes to greater intelligence but also increases the sensitivity of the individual to noise-induced hearing loss. You gave the example of sickle cell anaemia, which is a harmful mutation unless it's present in a region where malaria is common, at which point it is beneficial.
That doesn't mean you can't "take an embryo and just correct the obviously harmful genetic mutations" - correcting something like Cystic Fibrosis would be wonderful. And the ideal in the case of Sickle Cell Anaemia is obviously to correct for sickle cell after getting rid of malaria. But most mutations/polymorphisms are not as simple as that. I guess what I'm saying is that the distinction is a great deal murkier than "polymorphism = neutral, common" and "mutation = bad, rare", and the choice of which version of a polymorphism to have in your kid, if we ever come to that point, is not going to be as simple as it would be in the rare case of CF.
I agree that some polymorphisms have deleterious effects, but I do think we need an explanation for why they've survived and spread. Either they're very new or they have positive pleotropic effects; even CF is supposed to protect against cholera. Or in the deafness case, they only show up after reproductive age and so are probably evolutionarily inert.
Why do you think harmful mutations are mostly polymorphisms? If the mutations are random copying errors - that is, any genetic base is as likely to mutate as any other - then why would people be likely to share them?
Your third paragraph is correct as regards polymorphisms, but I don't think it's correct as regards "typos". The whole point of drawing that distinction is that the latter are unlikely to confer any beneficial effect, because most random changes to a working program are purely harmful.
« . I think I just realized why ugliness is unattractive. If there is a standard alignment for facial features then deviation from that alignment will correlate with high mutational load, and it will be a useful signal for the opposite sex that you are genetically inferior »
It sounds a bit simplistic.
I read recently an interesting explanation of why ugliness still exist, despite the fact that we would expect ugly people to reproduce less : The features that are attractive to women on a man and those that are attractive to a man on a woman are quite different, but there's no genetic correlation between these features and sex.
For example, a woman will find a man attractive because of his square jaw.
If they have a kid, the kid may inherit this square jaw, which is good news if it's a boy, but not if it's a girl, as it'll make her look manly, and presumably less attractive to men.
So many genes aren't bad in themselves so much as winding up in an unfavorable context.
2012-12-09 04:10 pm (UTC)
These are called antagonistic genes (sexually antagonistic genes in this particular case) and are, for one thing, probably behind the genetic portion of (male) homosexuality - there is a gene that causes hyperfertility in women, and homosexuality in men. Oh yeah, important thing to realize there: the same gene might not do the same in a man as in a woman.
2012-12-09 04:18 pm (UTC)
One dyslexic mistake
You say "parental age", your link says "paternal age". This also affects your later quip: polygynous societies tend to have lower maternal but higher paternal ages.
Others have pointed out that beauty is a cultural construct. A kind but "ugly" person may have greater attractiveness and overall better life-chances than a symmetrical person who is cold and angry.
This is all, vastly, a first-world construct, as well, and one which doesn't factor capitalism, gender inequity, class, or regulatory failure into the model - but very, very thoughtful. Thank you!
There seem to be certain features of beauty that are culture-independent (facial symmetry) and others that are culture-specific (like hair color). I would expect that even the culture-specific ones might be genetically driven in that there's a genetic mechanism by which whatever features are most common in that culture become a standard for beauty.
> (whoa. I think I just realized why ugliness is unattractive. If there is a standard alignment for facial features, then deviation from that alignment will correlate with high mutational load, and it will be a useful signal for the opposite sex that you are genetically inferior and should not be mated with. I assume someone else has figured this out before.)
Oh yes, that's an old idea. I think Miller proposed it a decade back or so; I do know that the Buss 2005 evopsych textbook covers the 'facial symmetry as indicator of mutational load & general health for sexual selection' thesis.
Some further reading: https://plus.google.com/103530621949492999968/posts/d4ZN53cGSTZ
As part of the Personal Genome Project and George Church's Lab, I have a lot of expertise in both the field of human genome interpretation and the technologies relevant to human genome improvements. I have many items I would be happy to comment on. For example, I happen to know* that a "modal genome" as you describe here has been published: see "major allele reference sequence" in this PLoS Genetics paper: http://bit.ly/rsT9DW
In fact, my comments would be so long, I think a livejournal comment here would be inappropriate. I'd be happy to write up my thoughts on various topics, shared as a post on my own blog. I love sharing knowledge but don't have a lot of free time, so I'd like to hear from you that this is something you think you'd find valuable before I spend time on it.
* (In part because I am a co-author on the paper.)
Well *I'd* certainly be interested in hearing more about that - can we reliably tell the difference between "bad" mutations (or rare variants), and "good" ones? I know that many variants include tradeoffs, but also that natural selection won't automatically weed out purely negative mutations if their effect is small enough.
You cannot engineer a car that would be ideal for track racing, off-road racing, grocery shopping and top mileage contests at the same time. Best track racing cars *have* to be bad off-road, there's no way around that.
Similarly, it can be argued that you can not genetically engineer a human that would be a genius in all kinds of science and all kinds of arts (and be a good person) all at the same time. That doesn't mean we can't engineer objectively better humans (same way as we can engineer objectively better cars), but there can be *more* genetic differences between an objectively better Einstein and objectively better Shaq than there are between real-world Einstein and real-world Shaq.
I understand where you're coming from, but I'm saying that according to this theory, that's not the case.
Imagine that we took a hundred cars and hit them with a sledgehammer d20 times. It might be that most of the variation in these cars on every dimension comes from what number they got on the d20.
Even a car that was originally optimized for off-road might be worse at off-road than a car originally optimized for track if we hit it with a sledgehammer enough times.
I'm wondering whether some genes are at their best in specific combinations so that evaluating one gene at a time might miss a lot.
2012-12-10 06:24 am (UTC)
Doesn't sound like a plausible explanation of intelligence heritability to me. If that were the only cause of intelligence differences, then how would humans have evolved higher levels of intelligence from our evolutionary ancestors? If the only thing making some proto-humans smarter than others was a difference in mutational load, then selection pressure for increased intelligence could only have resulted in a decreased mutational load. But Homo sapiens has large scale neurological differences from our ancestors. Unless some time in recent evolutionary history we finally hit upon the Perfect Brain, which cannot be evolutionarily improved upon, the hypothesis doesn't really make any sense.
I'm not saying this caused proto-humans to be smarter than apes. I'm saying that proto-humans evolved certain intelligence genes, and that variation within the human population is (at least partly) determined by how many of those are working optimally in any given individual.
2012-12-10 06:37 am (UTC)
It seems to me that you are lead astray in a number of places by reifying mutational load. This is most clear here:
(whoa. I think I just realized why ugliness is unattractive. If there is a standard alignment for facial features, then deviation from that alignment will correlate with high mutational load, and it will be a useful signal for the opposite sex that you are genetically inferior and should not be mated with. I assume someone else has figured this out before.)
If mutational load varies randomly in a population*, then it is the sum of different types of mutational loads that vary independently. Knowing that someone has a particular mutation does not tell you about whether they have any other particular mutation. If separate mutations affect appearance and other aspects of fitness, they are not correlated. But if most individual mutations have many effects, perhaps by small impairment to core systems like metabolism, then the effects on appearance tell about effects on other aspects of fitness. However, if you make that additional assumption, mutational load is no longer necessary to mention. Indeed, I have seen people put forward this hypothesis without mentioning mutational load.
*If you have two populations with different mutational loads, then appearance would allow you to identify the population, and thus the mutational load. However, diverse mutational loads requires reproductive isolation, so you would not expect selection for being able to identify the populations.
For example, West Hunter presents evidence that load is affected by parental age; older parents pass more mutations on to their children, so cultures in which people marry very young should have lower load than culture that encourage people to marry when they're older (yikes! Mohammed was right!)
West Hunter explicitly says that Mohammed is wrong by exactly this measure.
"older parents pass more mutations on to their children"
Amusingly, this could be a justiification for aristocracy.
If parental age is related to mutational load, is related to intelligence and other positive traits, and these overall negative mutations and generally inherited, then passing land, titles, etc. primarily to first-borns, who do likewise, eventually creating a ruling class actually makes a lot of sense, barring inbreeding which does more harm than good.
It would be interesting to collect a bunch of wild mice (in a region? worldwide?), create modal mice, release them into the wild, and see how they do. However, there might be some ethical difficulties.
Perhaps it would be better to start with coatimundis or some other animal which isn't such a direct competitor.
They'd just revert to ordinary mice within a generation because environmental mutations would keep happening on the n+1 generation
Lois McMaster Bujold's mileu has this, with gene cleaning being a standard mature technology applied to babies, as well as being raised in uterine replicators.
Read up on epigenetics, it's likely the uterine replicator providing a stable, optimized enviroment for fetal development is going to have much more of an effect than random gene fixes for stuff that is hardly visible in the phenotype anyway.
Also as mentioned by other commenters, antagonistic genes from mom and dad that work in opposition to each other also likely to remain a source of human imperfection.
I recommend you check out the youtube videos of Stanford's Dr. Sapolsky's lectures, he goes into this stuff in depth, and it's very fascinating stuff.
2012-12-12 08:20 am (UTC)
ncusgxj http://www.saclongchampsolde.eu orqabqn [url=http://www.saclongchampsolde.eu]sac longchamp pas cher[/url]rckhxoz
upsghzv mvncuit http://www.gafasdesolraybanbaratas.com ntemose [url=http://www.gafasdesolraybanbaratas.com]gafas ray ban baratas[/url]bkwnpgl
ospisfy http://www.lunettesdesoleilraybans.com kaccodo[url=http://www.lunettesdesoleilraybans.com]lunette ray ban pas cher[/url]clkxfyb
majayce http://www.guccioutletshops.com yboukau [url=http://www.guccioutletshops.com]Cheap Gucci Sunglasses[/url]pgjoeru
vldpliw http://www.sachermessolde.com tianlwv[url=http://www.sachermessolde.com]Sac Hermes[/url] kwnejrd
ajpotir http://www.stylomontblancsoldes.net qjgcguv[url=http://www.stylomontblancsoldes.net/]Stylo Mont Blanc Pas Cher[/url]fczliea
osgvlbe http://www.replicahermesbagsonline.net okobtxs[url=http://www.replicahermesbagsonline.net/]Replica Hermes Kelly Bags[/url]dyliuqf
kjpirvc http://www.mulberryoutletsonline.net kzvafht[url=http://www.mulberryoutletsonline.net/]Mulberry Handbags[/url]ezbdxkm
taydwhv http://www.louisvuittonoutletonlineshops.com lyckgoe[url=http://www.louisvuittonoutletonlineshops.com/]Louis Vuitton Outlet[/url]
lxmeozk http://www.sacguccisolde.com yifzvhp[url=http://www.sacguccisolde.com/]Sac a Main Gucci[/url]totoaoh
bphtjgi http://www.saclouisvuittonsolde.com dqnqtdi[url=http://www.saclouisvuittonsolde.com/]Sac Louis Vuitton Pas Cher[/url]frczxsj
klgvbed http://www.raybansforsales.com wywsvuq [url=http://www.raybansforsales.com]Ray Ban Aviator 3025[/url]kcvvxam
rcpbxzt http://www.montblancpensonlinesale.com pvmuolh[url=http://www.montblancpensonlinesale.com]mont blanc pens[/url]wyslbzc
2012-12-12 09:12 am (UTC)
where can i buy a cheap beats by dre headphone online
cdfva [url=http://www.cheapbeatsuksale.co.uk]dre beats solo hd[/url] vtmilg http://www.cheapbeatsuksale.co.uk bhgn [url=http://www.cheapdrebeatssales.co.uk]beats by dr dre[/url] mwavgj http://www.cheapdrebeatssales.co.uk lgzb [url=http://www.beatsbydreukstores.co.uk]dr dre[/url] htthxf http://www.beatsbydreukstores.co.uk scybl kdine qw [url=http://www.focsa.org.au/myreview/beatsbydre.phtml]beats uk[/url] vdxpnj un http://www.focsa.org.au/myreview/beatsbydre.phtml qxhru cp barou[url=http://www.drdrebeatsstores.co.uk]cheap beats by dre[/url] wfaacy http://www.drdrebeatsstores.co.uk gwrvwikcp [url=http://www.drdrebeatsuksale.co.uk]cheap beats by dre[/url] uixqbe http://www.drdrebeatsuksale.co.uk ygqb