Firstly, what makes you think viruses, yeast and flies are not relevant to the topic of mutation and evolution. Are you for real?
I did not say that. I said that they are prone to high rates of mutation - and that rates of mutation can differ greatly between species. Short-lived organisms that reproduce frequently have a much higher mutation rate than long-lived organisms that reproduce very infrequently. Viruses, yeast, and flies fall into the former category; humans (along with most mammals) fall into the latter. Using examples of the former to prove a high rate of lethal mutations doesn't necessarily apply to the latter.
Secondly, you didn't even read that same post and the array of evidence I carefully collected for you from different species INCLUDING HUMAN genetics!!!!:
Actually, I did read it. It is possible that I missed something - as I said earlier, I do make mistakes, such as when I'm writing a lengthy response (or several lengthy responses, as was the case here). Even checking it over doesn't necessarily mean that I catch everything. But I did read your entire post.
Now tell me who is blowing off who?
I did not blow you off. I thought I had responded to everything you wrote. It's certainly possible that I missed or misread something, but that is not the same thing as blowing you off. Which you did in this post: http://whywontgodhealamputees.com/forums/index.php/topic,25342.msg583856.html#msg583856
Having to deal with a flooded house is a good reason to not respond to a series of posts. It is not a good reason to respond to them by ignoring virtually everything I wrote and post more links. Though I will give you credit for going back and rectifying the situation.
Tell me seriously, why should I even bother helping you through your little patch of ignorance and stubbornness on this topic!
I am not ignorant on this subject. Where do you get off accusing me of ignorance, especially since I've posted my own information on this subject? That illustrates a very serious problem. You are assuming that I am ignorant, and therefore that I have to be 'helped' to become not ignorant. But that is not the case. As long as you continue to assume that my responses here are due to stubborn ignorance, we're not going to get anywhere.
Do you have the humility to apologise when you are wrong!
In fact, I have apologized for mistakes I've made in the past. What about you? Are you willing to acknowledge that part of this problem is due to your own assumption that I'm ignorant on this subject, and the condescending attitude you've thus adopted?
Why don't you read what I posted - long before you went to the smite button.
I gave you a smite because of the condescending and dismissive attitude you displayed here:
Then take your objection up with the scientists who are saying it. To be honest Jaimehlers you are tiring me - I actually don't have time to engage in a piss-ant debate with you, I have urgent and productive things to do right now.
I've explained my case and brought you evidence as I promised - so here are some quotes for you to digest:
This came across quite clearly that you didn't feel it was worth your time to even bother responding to what I wrote. As far as I'm concerned, you deserved that smite - not because you had other things you needed to do (I'll certainly admit that dealing with a flooded home is more important than responding to someone on a website, though it would have been nice if you would have actually said that), but because you threw a bunch more links at me even though you had more "urgent and productive things to do".
How that came across was, "I have other things to do right now, so I'm not going to read or respond to your post - but here's a bunch of links that I think you should read". Think about how that comes across - you're too busy to actually read what I wrote, but you're not too busy to find more stuff that you think I should read.
Is your mind open to learning from somebody else?
Of course it is. I did learn things from what you wrote. But learning things from you doesn't mean I'm going to discard other things I've learned and absorb whatever you say like a sponge.
I separated the link to the paper you quoted because I didn't want to risk it getting lost in the middle of the rest of my post.
The difference in the number of rare vs. common alleles was used to estimate that 79–85% of amino acid-altering mutations are deleterious (Kimura 1983). http://www.genetics.org/content/158/3/1227.full.pdf
The mistake I made here was addressing both this and the follow-up link to the Wikipedia page on harmful mutations at the same time. So I will be addressing it specifically.
It is worth quoting some other remarks from this paper.
WHILE the fixation of adaptive mutations may be viewed as the crux of Darwinian evolution, it has long been argued that the majority of DNA changes that accumulate over time are not adaptive but neutral, fixed by stochastic fluctuations in a finite population (Kimura 1983).
The proportion of mutations that are deleterious has been estimated from both allozyme and DNA divergence data. Negative selection prevents deleterious mutation from reaching common frequencies and so should produce an excess of rare variation. In humans, the number of rare (<0.5%) allozyme alleles is much greater than expected under neutrality in an equilibrium population (Kimura 1983).
This is where your quote comes in. Kimura's argument was basically that the number of rare variations was too high, and thus was likely produced by a much higher proportion of deleterious mutations (thus the estimate that 79-85% of amino acid mutations were deleterious). However, the paper goes on to say:
However, a recent increase in human population size can also account for the excess of rare variants. Negative selection also lowers the ratio of amino acid to synonymous divergence between populations and this ratio can be used to estimate the proportion of amino acid-altering mutations that are deleterious. Divergence of 46 genes among hominid species was used to estimate that 38% of amino mutations are deleterious (Eyre-Walker and Keightley 1999).
It does note that this might be an underestimate, though.
In short, I'm beginning to wonder if you read the whole paper. If you had, you would have realized that it goes into a lot of detail about the study that Fay, Wickoff, and Wu performed, and is an attempt to show a more up-to-date estimate of the deleteriousness of amino-acid mutations, rather than relying on those from older studies - which is what you quoted from the study.
Given the complexity of the study, I'm just going to try to focus on the latter part - where they discuss their findings. It seems that they do, in fact, estimate that roughly 80% of amino-acid mutations are deleterious (thought that includes all categories from slightly to lethally). Indeed, they estimate that there are hundreds of deleterious amino-acid mutations in each individual - suggesting that most deleterious mutations are not sufficiently harmful to kill off the individual carrying them. This is probably due to a combination of factors, such as whether the mutations occur on coding or or non-coding fragments of DNA, whether the deleterious mutations actually have an effect due to environmental changes, and just how deleterious the mutation actually is.
In short, it isn't enough just to show that deleterious mutations are common
. You need to show that deleterious mutations that have lethal effects are common, a much more challenging proposition. It's also important to note that a mutation that is deleterious under some circumstances can be neutral under others and even beneficial under some - thus helping to account for how mutations in general seem to be neutral even though they are classified as deleterious. Another factor is so-called 'silent' mutations, mutations that are either not expressed or are expressed in a way that doesn't make a noticeable difference in function.
One thing I didn't see in the study that I would be very interested to find is whether they were just testing mutations that made a noticeable difference, or whether they were testing all mutations. I'll freely admit that most mutations that are expressed are probably going to be deleterious - so the question is whether mutations that are not expressed would be considered deleterious or not.