Alien DNA

If something is on another planet it would have different environments. It would inevitabley Evolve differently as to that seen on Earth. So I ask, Would it have DNA?

This touches on what I am asking..

[edit on 25-01-2004 by Gear]

Originally posted by Gear
So I ask, Would it have DNA?

The simple answer is yes. How else would a living organism produced the cell structures and chemicals required for sustained life and growth?

Now the tough question to answer is would the DNA be the same as ours. Would it have the same number of nucleotides? Would it have more or les than the 4 that humans have?

Originally posted by Gear
If something is on another planet it would have different environments. It would inevitabley Evolve differently as to that seen on Earth. So I ask, Would it have DNA?

This touches on what I am asking..

[edit on 25-01-2004 by Gear]

I see what your saying it would have to have something similar to DNA but it could most possibly be composed of different chemicals. so it couldn't be called DNA. also the alien life could be mechanical or even energy based so it wouldn't even be similar to us.

Are there any organisms on Earth that don't have DNA? I'm not aware of any; even viruses have DNA. If anyone is aware of any, please post.

When it comes to extraterrestrial life however, we can't be sure until we encounter it. I assume all life would have to have some way of reproducing, and DNA is like a set of instructions that tells the cell how to do that. I think aliens would have to have DNA or something analogous to it.

People have legs, birds have wings, snakes slither, but they all get around in their own way. It's a different method in each case, but it gets the job done. My theory is it would be the same in this case. Aliens might not have a form of DNA that we would recognize, but I think they'd have to have something that served the same purpose. As for things like nucleotides, they are probably different, but, then again, the ones we have are stable, so it seems reasonable that they could form elsewhere, also.

I am fairly certain, however (as certain as I can be under these circumstances) that most/all alien life will also be carbon based, due to the chemistry involved. Some people theorize that life could develop based on other atoms such as silicon or germanium, since they are tetravalent as carbon is, but I'm not one of them. So if alien biology is based on carbon, it should be at least remotely recognizable to earth scientists, which, returning to the original topic, probably means DNA or something akin to it.

I think it can be pretty certain to say that every living creature in the universe has some kind of DNA. DNA and RNA are the essence of life. They are what carries information from one generation to the other.

Now, the number of nucleotides is likely 4, but who knows? We don't know anything else so far.

About the number of chromosomes, no one can say: it can be higher or lower, it doesn't mean a thing. So many creatures on earth have more than 43... So far, we're still the smartest. So far!...

Everything has DNA. It's the grand organizer of complex, multi-cellular beings.

The obvious answer to your question would be to find life and examine it. We believe that DNA is universal only on the premise that DNA has been found in every organism here on Earth. So life as we percieve it, should consists of DNA, but whose to say that mother universe has not found another mechanism for life very similar to DNA in a far off place in the universe.

Originally posted by kyateLaBoca
(...)
but whose to say that mother universe has not found another mechanism for life very similar to DNA in a far off place in the universe.
(...)

That's right, but I think I said

Originally posted by SpookyVince
(...)
pretty certain to say that every living creature in the universe has some kind of DNA
(...)

which is precisely that. It could just be DNA, it could be about the same thing but with the same purpose... Our, and likely their, genetics or whatever it can be called, our or their nature has to be transmitted to the next generation, and that is precisely the role of DNA.


[Edit]
I posted some day something about the same ideas, as to know whether Si organic chemistry would be possible and maybe involve life...

Here is the post. Amantine provides an interesting link in that post, basically saying that it is not likely possible in our world, with our knowledge of life at least, but the paper doesn't erase the possibility that under some other circumstances that thing can be real. Interesting, really...

[edit on 30-3-2005 by SpookyVince]

so how do you explain prion diseases ATSers. No genome there. Transmissable. Alive in some way. Do I have Mad Cow? Chacob Creutzfeldt? or perhaps nanobacteria induced coronary artery disease
Our model/definition of "life" is not nearly as straightforward as we often believe.

[edit on 30-3-2005 by bookie]