Shouldn't we be extinct according to population genetics?

[Anonymous No.12367169]

Every newborn has between 50-70 de novo mutations in his genome, mainly depending on the age of the father at conception.

2% of the human genome coding dna, but the total portion of the genome wich is subject to purifying selection is something like 5-10% of the total.

It follows that around 5-10% of those new mutation per newborn human have an effect on fitness, with the vast majority of them being deleterious (even if many of those very lightly so i. e. being a redhead or mild myopia).

Now, to maintain fitness in a population every deleterious mutation must be eventually eliminate from the gene pool through the disadvantage in fitness that its carriers have.
But I don't see how a species with such high intergenerational time and that produces quite a limited number of offspring could ever do so. 5% of 50 gives us 2.5 deleterious mutation per newborn. An unreasonably high percentage of people should fail to reproduce and women should have tons of kids for fitness not to decrease.
I read a paper by Michael Lynch that calculated at 5% the per generation loss of fitness of humans due to de novo mutations (I will post it if I find it).That's a lot.
Am I missing something in all of this?

[Anonymous No.12367200]

*fail to reproduce per generation

Here's the link

https://www.pnas.org/content/107/3/961

>per-generation reduction in fitness due to recurrent mutation is at least 1% in humans and quite possibly as high as 5%.

[Anonymous No.12367217]

Btw didn't take into account synonimous point mutations but whatevs, not important

[Anonymous No.12367536]

>>12367169
De novo genes are not that much of a problem.

Problem is how you approach them.

[Anonymous No.12367543]

>>12367169
>An unreasonably high percentage of people should fail to reproduce and women should have tons of kids for fitness not to decrease.
This was the world before the industrial revolution.
Now we are living the era of de-gene-ration, but soon advancement in genetics will repair all the little mistakes in the code.

[Anonymous No.12367574]

>>12367169
Fertilized egg != newborn baby
The ones with deleterious mutations die before they're born

[Anonymous No.12367631]

>>12367574
No they don't you fucking retard. What the fuck could possibly go through your mind to come to this conclusion?

[Anonymous No.12367667]

>>12367631
Yes they do, at least 14% and possibly as high as 65% of fertilized eggs end in a miscarriage or failed implantation. The 14% is is known pregnant women that end in a miscarriage. 65% is from in vitro studies of how often an egg is fertilized versus the known rate of .1% per copulation of resulting in viable pregnancy.

[Anonymous No.12367893]

>>12367667
Dude it's per newborn not zygote.

Also worth noticing
>fetal mortality has declined by approximately 99% in England since the 1500

A lot of mutations that would have resulted in a miscarriage now are survived to.

[Anonymous No.12369465]

>>12367893
Does that take into account that many fetuses are aborted after being tested? For example 100% of downs syndrome babies get aborted in Iceland.

[Anonymous No.12369689]

>>12367574
yeah you're right then this should not exist

[Anonymous No.12369773]

>>12369689
fuckin hell

[Anonymous No.12369827]

>>12367169
>2% of the human genome coding dna, but the total portion of the genome wich is subject to purifying selection is something like 5-10% of the total.
>It follows that around 5-10% of those new mutation per newborn human have an effect on fitness
No it doesn't, a mutation in a functional area doesn't mean the mutation will have an effect on function. The vast majority of mutations have no affect at all.

>Now, to maintain fitness in a population every deleterious mutation must be eventually eliminate from the gene pool through the disadvantage in fitness that its carriers have.
Why?

[Anonymous No.12369860]

>>12369827
>No it doesn't, a mutation in a functional area doesn't mean the mutation will have an effect on function

Either that part of the genome is subjected to purifying selection (even if a very weak one) or it's not and accumulates mutations freely.
>The vast majority of mutations have no affect at all.
Because the vast majority of our genome does nothing. According to the estimates in the paper every newborn carries from 0.9 to 4.5 fitness reducing mutations, so my numbers are close estimate I would say.

>Why?
Mutation selection balance.