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Snackbit's avatar

Has there been any research with regards to how to conceive a high fitness embryo without the use of embryo selection or sperm analysis, using the regular way of conception?

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Stig's avatar

Yes, the reverse cow girl will provide a gravitational pull which gives the strongest sperm cell an advantage. Also, make sure the sperm deposit is fresh, but not too fresh. 2-3 days is optimal

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StrayBullet's avatar

Unrelated to the post, but in Charles Murray's book "Real Education", I remember there was this one part where he went over logic questions and the percent of people who could answer them correctly. I think one of them was like, "If a company has 90 employees and it increases by 10 percent, how many employees do they have now?", and about 75 percent of people couldn't answer it correctly. It was used to show how intelligent people often over-estimate the ability of average people.

I think it would be cool if you made a post about the types of questions someone at the 50th percentile can answer vs. someone at the 95th percentile. The disparity between them would be more clear if people understood the types of questions they were able to solve.

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Lyautey's avatar

All hail the needle in the balls!

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L P's avatar

But isn’t every sperm sacred?

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David's avatar

Using technology like sperm washing, freezing and thawing, and other sorting technics based on shape, motility, etc are all good and should be done. But when we're talking about selecting from hundreds of millions of sperm cells, even getting the top 1% means ending up with thousands of potential candidates.

Assuming 100 eggs per IVF cycle. If a 18 year old woman undergo 5 IVF cycles per year for 5 years, we end up with 2,500. That's still a very small number compared to the 10,000 "good" sperm cells that we can get per sample. But I think it's good enough to be able to select the most important traits out of them. Anybody think that we can't find an embryo with the lowest risks for diseases, mental health, above average height, and most importantly at least +3 SD in IQ out of 2,500 embryos?

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Stig's avatar

As Emil found, 1,000 embryos does not give much extra over 100. But, that is for one trait. We would want to optimize over many traits. Let's call it a "social credit score" (SCS). The SCS would consist of many traits, like education, health, income etc. How would optimizing on such a score affect the sample size needed?

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David's avatar

Gwern wrote about this also:

https://gwern.net/embryo-selection#limits-to-iterated-selection-the-paradox-of-polygenicity

A lot of desirable traits tend to correlate. I know there's a correlation of height and IQ, so selecting for just IQ will also give you height "for free". But selecting for lower risks of mental illness or cancer might be completely orthogonal to IQ.

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Emil O. W. Kirkegaard's avatar

No, both of those also correlate positively with g.

https://www.emilkirkegaard.com/p/mental-illness-and-intelligence-the

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Stig's avatar

Yes, in some cases two preferred traits would have a negative correlation. (lack of) Autism and IQ is maybe one.

But, we could do something simple, like life time net income (subtract the cost from hospital usage etc). A government should be able to easily create a PGS for that.

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Kristo Veeroja's avatar

I am definitely willing to take a needle in my balls.

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May 4, 2023
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Emil O. W. Kirkegaard's avatar

Didn't know about that one. When I talked to a lot of people in stem cell research, they say that working with these cells is very difficult and expensive because they are very finicky. Because of this problem, maybe IES-like approaches is not so close after all. This would then mean that genomic sperm selection is a more fruitful approach in the short term.

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