alt Hacker NewsI am worried about the long term impact of research involving human conception, IVF, etc.
The reason is that genetics/evolution don't yet seem to fully explain how humans exist. A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human.
I suspect there are as-yet undiscovered effects which shape the next generation. Whether that be DNA methylation, gut bacteria passing from mother to child, selection of the 'correct' egg or sperm out of millions, or something new and un-discovered etc.
And if those effects are bypassed with artificial conception, we might end up with humans which aren't as strong, aren't as smart, aren't as well adapted to a changing environment, etc.
The effect will be small for each generation, but after 5-10 generations of a combination of artificial and natural conception you could end up with meaningful loss of fitness - or perhaps a lack of gain of fitness that would have otherwise occurred.
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25% of humans died before reaching 5 in 1800s US, today it is <1%. Its been at least 5 generations since this value dropped dramatically.
We have not ended up with "humans which aren't as strong, aren't as smart, aren't as well adapted to a changing environment, etc."
>I am worried about the long term impact of research involving human conception, IVF, etc.
You'd have a rather different opinion if you had to squeeze out a water melon out of your genitals.
You’re layering several hypotheticals on top of each other, which leads to progressively distant possibilities. Good on you for caring about humans though
Natural reproduction already has a lot of randomness and failure built into it. It's not like egg/sperm selection is a perfect quality-control system. IVF has also been around for decades, and while it definitely needs monitoring, we haven't seen some obvious collapse in health from it
> humans which aren't as strong, aren't as smart, aren't as well adapted to a changing environment, etc.
But can they pay and vote? If yes, that is good enough for the people calling the shots.
I think it’s important to remember that the process of selection acts directly on human traits. For example being exposed to high summer heat temperatures may eliminate some people who have unproductive sweat glands, or needing to run down your food may eliminate people who have a muscles that easily tire. Selection (largely) does not act on far removed traits like egg cell characteristics as a proxy of human traits like muscle performance because the genes that are used by egg cells are quite different than those used by muscle cells. So if you worry about some kind of human trait decline you should be much more worried that people have access to air conditioning and grocery stores.
> A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human.
What?... Our computers can't simulate anything similar to a real world. You're comparing apples to galaxies.
> meaningful loss of fitness
What makes you think we don't have "loss of fitness" already?
150 years ago child mortality was around 30% in the developed world, now it's less than 1%. A lot of kids with weak health survive now. I'm one of them - I got pneumonia when I was ~2 y.o. and probably would have died without antibiotics. Then I had something which required antibiotic treatment pretty much every year. My wife also had a pneumonia in early childhood. And so did my daughter...
Why do we need to talk about some mysterious problem in 10 generations when modern medicine removes a lot of fitness pressure by itself?
As I understand it, that they've gone back to the point of making the ovary and the egg itself is going through Meiosis helps here, because it's got the randomness of picking genes between the pair of chromosomes in the source. So it's not just a clone; it's a little more natural than if they tried to produce the egg directly.
Several of your claims are unsubstantiated. Sure, species co-evolve together, environment shapes evolution.
But why do you think evolution doesn’t explain existence of humans? What’s missing?
Also, as someone else has replied to you, we’re way past “natural” existence of humans. The vast majority of 8+ billions wouldn’t have survived in the past.
Very interesting...maybe this is another great filter preventing a species from becoming multi planetary or expanding beyond a type 0 civilization?
I'm far more worried about the long term impact of letting evolution exert its pressure on humankind unchecked.
> but after 5-10 generations of a combination of artificial and natural conception you could end up with meaningful loss of fitness
Yes, if we end up in some corner-case dystopia where evolution and natural selection continue to be in charge of fitness. But evolution and natural selection bring much suffering to the unlucky. In other words, if you go to a hospital, you'll quickly learn there's far more human suffering caused by God and Nature than by the "cruelty of man". Though common sense is never assured victory, I look forward to a world where our children live healthier and longer lives due to us properly messing with God and Nature.
That's a lot of words to act like a total tool towards people born from IVF and their parents.
>The effect will be small for each generation, but after 5-10 generations of a combination of artificial and natural conception
How do you know it? Sci-fi tropes are not a good argument.
There is nothing such as riskless technology, but you can't escape some risk anyway.
Tech like this gives some people a chance to be born. If they aren't born, this may damage the rest of the world in subtle, very hard to predict way. The invisible graveyard of medicine, caused by risk aversion, is real. In the name of safety, you may miss out on the next Freddie Mercury or David Attenborough, or Jonas Salk or Paul Erdös.
Also, the 5-10 generations you mention is 150-300 years in current humans. It is very unlikely that biological science will stagnate on current level of knowledge and blindly repeat beginner mistakes from 2026 for 150-300 years.
For comparison - 150 years ago, germ theory was still a contested newcomer. 300 years ago, medicine still believed in Galen's humor theory.
>The reason is that genetics/evolution don't yet seem to fully explain how humans exist. A computer genetic algorithm run for a billion generations doesn't lead to anything anywhere near the the complexity of a human.
I didn't have "creationism" as the top answer to a HN post in 2026, yet here we are...
I have noticed that lately certain topics on HN seem to be eliciting low quality comments like "genetics/evolution don't yet seem to fully explain how humans exist". That is a really ignorant and silly thing to say. Are we being flooded with AI generated comment slop or do topics involving genetics attract a less knowledgeable crowd?
Having gone through IVF multiple times, there’s usually a pretty rigorous process and it is highly regulated in many countries. In some places you need genetic screenings when using donors. I was unaware that I was carrying a mutation for a difficult to diagnose, fatal but relatively easy to treat disease if caught early, which explained at least two cases in my family history. If the donor happened to carry the same mutation, the chances of having an offspring with the disease was around 25%. So in my view, IVF if done right, could actually make healthier humans. And yes, this genetic screenings are available to anyone not only IVF patients, but it is extremely unlikely that people will use them when conceiving naturally, because first, they aren’t cheap and secondly there’s some sort of tabu about asking your partner for genetic testing, and even if the test comes back positive for some type of disease, what would people do anyway?