Petteri_Kiiskinen
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Found factual errors from my previous post, after doing last round of research. Should've done it before submitting...
The ova are not in haploid state for the lifetime of the female, but in diploid state, arrested at prophase of meiosis I. Couldn't find out how much cellular activity they have at this stage, but anyway, there is thus still one DNA replication at only a short period before possible fertilization. This renders much of my above argumentation mostly null. Indeed could be the DNA of ova and spermatozoa isn't expressed at all at the haploid cell. This would leave the pre-birth selection pressure only to spontaneous zygote abortions (which have other explanations than mere point mutations to them as well).
Eliezer, I have to admit I'm not studied on the field enough, and I've not read papers on this particular. The initial cell bodies of a gamete of course come from the parent cell.
However after that, they have to keep on living. And they do this using their own genetic material to support and repair themselves, manufacturing new cell bodies, enzymes and other constituting proteins as old bodies deterioriate. All ovum in ovaries are present at birth of the female, thus having to be able to maintain their function at least up to menopause. This makes them one of the longest living cells beside neurons, while being haploid at that. Of... (read more)
A point to note is that corrupting pressure to genome through adverse point mutations occurring on protein coding DNA regions are partly counterbalanced by selection happening already before birth, in form of miscarriages (late and early) and cell death or cell inefficiency during earlier stages of the germline development, even before fertilization.
Even if the value of 1 bit per generation holds true for addition of new 'relevant' information, the above acts as additional positive factor that only acts to negate the degrading effects of random mutations. Obviously this doesn't matter when talking about post-birth (meaning, say, post-one-week-after-inception, assuming only a lowly value of 50% of miscarrying after that point)... (read more)
Meh, not thinking straight anymore. There are no DNA replications at meiosis, although the recombination does happen here. But still, if there's no cellular activity during the arrested prophase, the DNA isn't tested anyway. Now I go to sleep, hoping I wont make any more mistakes.