Which came first the DNA, RNA or protein

[scottyiu]

Which came first the DNA, RNA or protein? i know there is no answer but can anyone give their thoughts on this? I am interested to know.

[cool A-level student]

well 1st off the molecules and elements which make it up would build up i guess.
and then form molecules, the smaller stuff at first like amino acids and RNA ect...
and would later develop into more complex molecules like DNA and proteins, i would GUESS that DNA came 1st as its the instructions to build proteins in the first place, but then again how did the ribosomes be built in which make proteins? its a rather confusin issue like which came 1st teh chicken or the egg, they need eachover to exist.

what do the rest of you think?

[Jelanen]

Speculation is that RNA was first since RNA does all the really cool RNA things and it can also be information storage like DNA.

-Jelanen

[Avalbane]

It had to start somewhere...even though RNA makes the proteins I'd say protein came first, because protein is the building block for organisms. Or, DNA, RNA, and protein all came into existance at once.

[canalon]

It had to start somewhere...even though RNA makes the proteins I'd say protein came first, because protein is the building block for organisms. Or, DNA, RNA, and protein all came into existance at once.

Well the problem is that you are thinking using analogies, and not a good one at that... There are many building blocks for living organisms, ans proteins are not the only one. As for the "DNA, RNA, and protein all came into existance at once", i would just suggest that you imagine how likely it is that such a thing happened. I certainly do not agree with Behe's irreducible complexity argument (simply an admission of intelectual if you ask me), but I am sure that the complexity was built one block at a time.
Then even though there is no proof that DNA came first (some suggested mineral crystals) we know for sure that we are looking for a self replicating molecules, and RNA which has the same replicating ability than DNA plus some catalytic activities really looks like the best candidates. Until proven wrong that is...

[scottyiu]

I have put a poll in the off topic section. So if you want to poll, go to the off topic section...

[nddionne]

any reference, anyone? need something for my thesis

[MrMistery]

Check any molecular evolution book(but of course, you won't find biochemistry books that detail opinions about the beggining of life at every street corner)

[victor]

I can think that the existance of DNA as our genetic information now is because of RNA's positive-feedback process..

[Jumpshooter]

*This is no longer a topic of debate, consideration,or experimentation amongst the modern research community--mainly because it does not matte which came first. The key Questons these days are: how do we reglate mutation in DNA? How can we inhibit RNA synthesis Reverse Transcriptase? This is mainly for drug discovery like herpes, HIV, and bird flu. At this point in our History of Science no one is really concerned about what came first. Sorry

[fleu]

maybe it isn't today the main topic but it is still useful to give some thought for the question. In our school we got this topic as a homework and it forces as to think about dna, rna and proteins in general. and I think it is useful....
Could someone tell me why protein didn't came first?

[fleu]

I mean if it didn't.. some arguments for protein?!