Impossible evolution of new beneficial proteins

Hi I am a Creationist and I have a question that will trouble you evolutionists.I will accept Gene Duplication as a mechanism for increasing the number of genes, but changing the duplicates into *new* genes with *new* *beneficial* function via mutation seems statistically impossible.In a gene of 250 amino acids there are 20^250 different combinations of amino acid sequences. The specific sequence determines the final 3D structure that makes up the protein. The 3D structure is critical to how the produced protein can interact in the body. Slight changes to a proteins 3D structure via one amino acid being changed can cause diseases.
The point is a change to the 250 amino acid sequence which results in a new 3D structure of the protein will produce a very different 3D structure.
At any stage, one point mutation in a 250 amino acid sequence can only change the sequence into a few hundred of the 20^250 possible sequences. What is the chance that any of these hundred sequences will fit snuggly in the organism and be beneficial and useful? Next to none. Instead we have to rely on point mutation after point mutation, without any selective driving force, eventually stumbling across a new beneficial protein sequence. That is statisically impossible and is a nightmare for evolution.

How are you calculating these odds? What do you mean when you say "useful and beneficial"? Beneficial with respect to what?First of all I must admit I am not calculating odds. This is more of a "what is the mechanism?" question where I am simply posing a potential problem for evolution.I am thinking of the genes which humans have and simple bacteria don't. To explain the origin of these genes often gene duplication is put forward as a favoured mechanism.But how possible is it to take an existing sequence and convert it into a new sequence via random mutation?
Surely the sequences of these genes are very different from one another, so it would take many many point mutations to go from one to the other. Surely such a hurdle is beyond chance when you consider that each intermediatery stage will have no benefit and cannot be sustained by natural selection.
Without natural selection the process becomes nothing more than trial and error, not a very convincing mechanism for design when you don't have infinite time.
In fact being neutral means there is no reason why one of these point mutations couldn't end up trashing the gene by overwriting its end codon before a useful configuration was reached

No I don't deny beneficial mutations.If you are saying that amino acid sequence can not be rearranged or truncated without losing function
Yesthen you are incorrect as well
AhThat's interesting, so you can effectively cut a lot of amino acids from an enzyme and it will still function correctly? thats pretty coolMy question to you is this, what is stopping the process of random mutation and natural selection from changing amino acid sequences in a way that confers increased fitness?Well I don't think natural selection is going to come into play until a useful sequence is reached. Until then you have to rely on random mutation just coming across a useful sequence by chance.While obviously I have nothing to base the numbers on I can make a rough calculation to show you what my point is:A 300 amino acid sequence has 20^300 different combinations. My understanding is that a large number of those sequences will not code for a protein useful to the organism.Lets say there are 20^100 useful sequences (and I think that is a conservative figure) for the organism within the search space, then it appears that for every useful protein sequence there are 20^200 useless protein sequences. So I would expect all the useful sequences to be reasonably far apart, seperated by useless sequences.
My point is that if these sequences are far apart, seperated by useless intermediatery sequences, then natural selection cannot "guide" mutations to a new sequence.Natural selection is perfectly able to improve a protein sequence, or preserve a protein sequence, but it is unable to guide a protein sequence for one function to a protein sequence for an entirely different function.Then again it could happen by chance via lots of mutations building up and chancing upon a new sequence (but if that was the case wouldn't it be more probable that the gene was damaged eventually?). I just wonder if anyone has done the maths on this or if we simply don't have the numbers to do the maths yet[This message has been edited by GreenBlue, 02-07-2004]